He studied classical philology at the Vilnius University in 1947–1952, receiving his Ph.D. in 1956 at the Lomonosov Moscow State University with his thesis on Lithuanian numerals. In 1955 he started working at the Vilnius University, holding a Chair of Lithuanian Language in 1968–1973.
Vytautas Mažiulis was also correspondent member of both the Mainz Academy of Sciences and Literature (Germany) and the Milanese Linguistics Society (Italy), as well as Chairman of an International Commission on Baltic-Slavonic Relations.
- Relations of Baltic and other Indoeuropean languages (Vilnius, 1970)
- Prūsų kalbos paminklai ("Monuments of the Prussian Language" Vilnius, t. I 1966, t. II 1981, Vilnius)
- Prūsų kalbos etimologijos žodynas ("Etymological dictionary of Prussian", 4 volumes, 1988-1997, Vilnius)
- Prūsų kalbos istorinė gramatika ("Historical Grammar of Prussian", Vilnius, 2004)
- On the Diachronic Morphology of the Slavonic and Baltic Languages (in collaboration with V. Zhuraviev, 1978, in Russian)
- Mirė pasaulinio garso baltistas prof. V.Mažiulis (World scale linguist, prof. V.Mažiulis dies) Archived 2012-08-18 at the Wayback Machine. Retrieved on 2009-04-14