Many countries, organizations, and individuals issued reactions to the death of Kim Jong Il in December 2011. According to CNN, reactions were "somewhat muted" in comparison to deaths of other world leaders. Just a few countries reacted immediately after Kim's death was announced on North Korea's KCTV. Some countries, like the United States, took the opportunity to comment on their relationship with South Korea. South Korea decided not to offer official condolences, mirroring both worsened relations after the ROKS Cheonan sinking and the bombardment of Yeonpyeong and its position after the death of Kim Il Sung in 1994. Chinese Foreign Ministry called Kim a "great leader" and added that Beijing would continue to offer its support. Japan expressed condolences and said it hoped Kim's death would not affect the region adversely. Reactions in Europe were "a mix of hope and watchfulness". In North Korea, the official reaction was grief and support for the succession of Kim Jong Un.

Korean peninsula Democratic People's Republic of Korea Korean Central News Agency announced the news, stating on 19 December:

Images showed that in the streets of Pyongyang, many people wept over Kim's death. People could be seen gathering to pay their respects, some kneeling, some wailing, and some beating the ground with their fists.

The BBC reported that the Korean Central News Agency said people were convulsing with pain and despair at their loss, but would unite behind his successor Kim Jong Un. They said that all party members, military men, and the public should faithfully follow the leadership of comrade Kim Jong Un and protect and further strengthen the unified front of the party, military, and the public.

Workplaces and local government offices have organised meetings to create a proper atmosphere of mourning. People's Units have emphasised the Last Instructions of Kim Jong Il and groups from schools and workplaces have been visiting statues of Kim Il Sung and other major memorials to pay their respects."People Cried and Wailed", Lee Seok Young, Daily NK, 19 December 2011

Republic of Korea After the death was announced, the South Korean military was put on high alert. The South's National Security Council, worried that political jockeying in North Korea could destabilise the region, also convened for an emergency meeting. President Lee Myung-bak cancelled the rest of his Monday schedule and in a statement, declared, "[f]or the sake of the future of the Republic of Korea, peace and stability on the Korean Peninsula is more important than anything else. It should not be threatened by what has happened. We must make thorough preparations to maintain peace and stability and continue to work closely with the international community ... All citizens are asked to go about their lives without wavering so that peace and stability on the Korean Peninsula will not be hampered". No government officials from Seoul paid condolences, according to the Unification Ministry. Lee Hee-ho, the 89-year-old widow of former South Korean President Kim Dae-jung, and Hyundai Group Chairwoman Hyun Jeong-eun led a private group of 18 South Koreans on a two-day visit, where state media showed them being greeted by Kim Jong Un on 26 December.

Supranational bodies European Union – Catherine Ashton, the High Representative of the Union for Foreign Affairs and Security Policy, said that "the EU is monitoring the situation closely and is in contact with its strategic partners with a view to sharing assessments on the possible implications". In the name of all EU countries, the Polish diplomat signed the condolence book in Pyongyang. – A spokesman for U.N. Secretary General Ban Ki-moon said, "The Secretary-General extends his sympathy to the people of the DPRK at this time of their national mourning. The Secretary-General reaffirms his commitment to peace and security on the Korean peninsula. The United Nations system will continue to help the people of the DPRK. The Secretary-General is closely following the situation".

Governments – President Serzh Sargsyan sent condolences. The message was reported to have been addressed to the DPRK's president, who would in fact be the Eternal President of the Republic Kim Il Sung, who died in 1994. – Called on governments, including North Korea's, for "calm and restraint" in the aftermath of Kim Jong Il's death, and also urged the DPRK to "engage with the global community". Foreign Minister Kevin Rudd stated, "[i]t is at times like this that we cannot afford to have any wrong or ambiguous signaling. This time also presents an important opportunity to the new North Korean leadership to engage fully with the international community. On how to improve their economy in order to properly feed their people and critically on how to deal with the outstanding problem of North Korea's nuclear weapons programme". – President Ilham Aliyev sent a letter to Kim Yong-nam, Chairman of the Presidium of the Supreme People's Assembly, which stated, "I was deeply saddened to hear about the death of the prominent statesman, Supreme Leader of the Democratic People's Republic of Korea, Chairman of the National Defence Commission, Kim Jong-il. On behalf of myself and the people of Azerbaijan, I expressed my deepest condolences to you, to the family of the deceased and to your people over this heavy loss". – President Zillur Rahman and Prime Minister Sheikh Hasina each sent their condolences to North Korea over Jong-il's death. "The people of DPR Korea have lost a great leader and we have lost a dear friend", President Rahman said. Prime Minister Hasina said, "Our hearts are with the members of the bereaved family and the people of DPR Korea and we pray that they will be able to bear this irreparable loss with courage and fortitude." – President Alexander Lukashenko sent his condolences to Kim Jong Un over his father's death. – "Kim Jong-il has died, but the friendship and bilateral cooperation between North Korea and Cambodia will never die", a spokesman for the Cambodian Council of Ministers said. The spokesman continued, "North Korea is a sovereign country and can make whatever political decisions it needs to for the good of their land – they know what is best for them. But for us, we have a relationship that has been improving, and over time this has opened up many opportunities for bilateral trade". Meanwhile, the Minister of Information Khieu Kanharith said the death of Kim Jong Il was a "great loss". Kanharith added, "We hope that (Kim's) plans to act as a mediator for reconciliation of the two Koreas continue in the interest of the peninsula, Asia and the world". – Prime Minister Stephen Harper said, "Kim Jong Il will be remembered as the leader of a totalitarian regime who violated the basic rights of the North Korean people for nearly two decades. We hope his passing brings positive change allowing the people of North Korea to emerge from six decades of isolation, oppression and misery. ... At this critical juncture, we urge North Korea to close this sad chapter in its history and to work once more towards promoting both the well-being of its people and stability on the Korean peninsula.” – Foreign Minister Yang Jiechi met with Pak Myong-ho, chargé d'affaires of the DPRK Embassy in Beijing. He expressed the belief "the DPRK people would remain united with the leadership of the Workers' Party of Korea and comrade Kim Jong-Un, turn their sorrow into strength, achieve new progress in socialist construction, and make new contributions to realizing the sustainable peace and stability of the Korean Peninsula". Foreign Ministry spokesman Ma Zhaoxu called Jong-il a "great leader" and added Beijing would continue to offer its support and make "active contributions to peace and stability on the Korean peninsula and in this region". – President Ivo Josipović expressed condolences to the citizens of DPRK and said, "Dear HE Kim Jong-un, I, on behalf of the people of the Republic of Croatia and on my own, express condolences on the demise of the great leader of the Korean people HE Kim Jong-il, general secretary of the Workers' Party of Korea, chairman of the National Defence Commission of the DPRK and supreme commander of the Korean People's Army. I extend condolences to all the people of the DPRK". – "Cuba's Council of State has declared official mourning due to the passing of comrade Kim Jong-il", an official statement said, noting that Cuba's flag would be flown at half staff from 20 to 22 December. – President Teodoro Obiang Nguema Mbasogo expressed his and the Equatoguinean people's "deepest condolences" regarding Kim Jong Il's death in a letter addressed to Kim Jong Un. – "At this hour of mourning, we express our heartfelt sympathy and deep condolences to the people and government of the DPRK", President Girma Wolde-Giorgis wrote in a letter of condolences addressed to Kim Jong Un. – The Minister for Foreign Affairs Erkki Tuomioja said in an interview that "Kim Jong-il probably won't be missed by most people" and expressed concern about the ruling elite strengthening its grip in fear of unstable consequences. President Tarja Halonen, however, expressed empathy for the close ones of the deceased and wished for democratic reforms. – The Foreign Ministry released a statement saying that France "reaffirms its commitment to peace and stability in the peninsula and hopes the North Korean regime will evolve in a positive way... Our thoughts go to North Korean people who have been suffering for years from misery and lack of human rights... France will carry on its action for North Korean people, especially by supporting humanitarian programs..." Also, French Foreign Minister Alain Juppé is quoted as having said, "There isn't much hope. It is a completely closed off regime ... We are very cautious about the consequences of this succession. We hope that one day the North Korean people will find freedom. There are ongoing talks with North Korea ... and we need to keep on talking with China and other participants to make North Korea abandon its nuclear weapons". – Foreign Minister Guido Westerwelle said, "We hope that a window of opportunity will open for the people of North Korea". Foreign Ministry spokesman Dirk Augustin told journalists, "This is, of course, a chance for things to change there, but our expectations remain the same: That North Korea gives up its nuclear program, that the catastrophic social situation of its own people improves and that it declares itself ready to open up in the political and economic spheres. Whoever takes over power must assume responsibility for improving the desperate situation of the people there. There is a clearly untenable situation with two Korean states". – President John Atta Mills, on behalf of himself and the Ghanaian people, expressed condolences to Kim Jong Un, the government, and people of the DPRK over the demise of Kim Jong Il. Mills also said that Ghana is confident that the "DPRK will advance in unity to attain the goal of building a thriving socialist nation under the leadership of Kim Jong-un, the great successor, and the Workers' Party of Korea". – President Alpha Condé addressed a letter of condolences to Kim Jong Un, saying, "It was with great sorrow that I heard together with the Guinean people the sad news that Kim Jong-il, General Secretary of the Workers' Party of Korea, Chairman of the DPRK National Defence Commission and staunch guardian of the noble cause of the Korean people, passed away. At this moment of grief I, on behalf of the government and the people of Guinea and on my own, express the most profound condolences and ask you to pass my sincere condolences on the brave Korean people.