MUI, Mui, or mui may refer to:
Computing Magic User Interface, system to generate graphical user interface Multilingual User Interface, Microsoft's technology and file name extension for multiple languages on a Windows system
Organizations Indonesian Ulema Council (), Indonesian Muslim clerical body. Muhammad University of Islam MUI Group, Malayan United Industries.
Places Mui (मुई), a village in Sawai Madhopur district, Rajasthan Mui River in Ethiopia Mui, Estonia, a village
People Constance L. Mui (born 1959), American philosopher Kong Duen-yee, known as Mui Yee Mei (surname), Chinese surname Peter Mui, American fashion designer
Economics Matter Under Inquiry, a preliminary investigations by the US Securities and Exchange Commission Men's underwear index, an economic index
Other uses mui, ISO 639 code for the Palembang language also known as Musi
See also Muy (disambiguation)