Mungiu was born in Iași. His sister is political analyst Alina Mungiu-Pippidi. After studying English literature at the University of Iaşi, he worked for a few years as a teacher and as a journalist. After that, he enrolled at the University of Film in Bucharest to study film directing. After graduating in 1998, Mungiu made several short films.

In 2002, he debuted with his first feature film, Occident, which enjoyed critical success, winning prizes in several film festivals and being featured in Director’s Fortnight at the 2002 Cannes Film Festival.

In 2007, Mungiu wrote and directed his second feature, 4 Months, 3 Weeks and 2 Days. The film was received enthusiastically, attracting critical praise and being selected in the official competition at the 2007 Cannes Film Festival, where it won the Palme d’Or for feature film, marking the first time that prize was awarded to a Romanian filmmaker.

His 2012 film Beyond the Hills was screened in competition at the 2012 Cannes Film Festival where Mungiu won the award for Best Screenplay and Cristina Flutur and Cosmina Stratan shared the award for Best Actress. The film was also selected as the Romanian entry for the Best Foreign Language Oscar at the 85th Academy Awards, making the January shortlist.

In 2013, he produced the next film of Nae Caranfil, 6.9 on Richter. In April 2013, he was selected as a member of the main competition jury at the 2013 Cannes Film Festival.