- Wanted to become a musician in college but decided to get into directing after watching The Godfather (1972) and The Claws of Light (1975).
- Wrote a script for late Fernando Poe Jr. after winning the FPJ-Mowelfund Screenwriting Contest that was sponsored by him.
- Moved to the United States in 1992 where he worked for a community newspaper before directing the critically-acclaimed Batang West Side (2001).
- Won a Gawad Urian award for Evolution of a Filipino Family (2005).
- Received the Orizzonti Grand Prize at the 65th Venice International Film Festival for Melancholia (2008).
- In 2008, released his first solo album, Impiyerno: Songs From & Inspired by the Cinema of Lav Diaz, at the 3rd .MOV International Digital Film Festival.
- Directed Norte: Hangganan ng Kasaysayan (2013) that was screened in the Un Certain Regard section of the Cannes Film Festival; was the country's official entry to the Oscars that year.
- Won the Golden Leopard at the Locarno Film Festival for Mula Sa Kung Ano Ang Noon (2014).
- Well-known for making lengthy films; his Evolution of a Filipino Family (2004) was 593 minutes long.
- Has been dubbed as "the ideological father of the New Philippine Cinema" by the Venice Film Festival.