Petar Šain (1885–1965) was a Bosnian artist. He was one of the first generation of art school trained painters which included Gabrijel Jurkić, Petar Tiješić, Karlo Mijić, Špiro Bocarić, Đoko Mazalić, Roman Petrović and Lazar Drljača.
- The Grove encyclopedia of Islamic art and architecture: Volume 2 - Page 301 Jonathan M. Bloom, Sheila Blair - 2009 "At the exhibition of Bosnian artists in Sarajevo in 1917 Karlo Mijić (1887–1964) exhibited his first engravings and Petar Šain (1885–1965) was represented by his wood-carvings."
- The Art treasures of Bosnia and Herzegovina ed. Đuro Basler, Mirza Filipović, Sulejman Balić - 1987 "..and Petar Sain (1885-1965), a faithful follower of ..."