Charles Day may refer to:
Boots Day (Charles Day, born 1947), former baseball player Charles Day (boot blacking manufacturer) (died 1836), founder of Day and Martins Blacking Charles Day (Medal of Honor) (1844–1901), American soldier in the American Civil War Charles Day (engineer) (1879–1931), American engineer and co-founder of Day & Zimmermann Charles Day (rower) (1914–1962), American rower Charlie Day (Charles Peckham Day, born 1976), American actor Charles Bernard Day (born 1957), American judicial nominee Charles Dewey Day (1806–1884), Canadian judge Charles W. Day (1836–1906), Wisconsin state senator from De Pere, Wisconsin Charles Wayne Day (1942–2008), American blues guitarist