Petras is a masculine given name. It is a cognate of Peter, which is derived from the Greek word "petros" meaning "stone, rock". People with the give name Petras include:

• Petras Auštrevičius (born 1963), Lithuanian politician, diplomat, civil servant
• Petras Balocka (born 1986), Lithuanian basketball player
• Petras Ciunis (1898–1979), Lithuanian army officer, educator
• Petras Cvirka (1909–1947), Lithuanian author
• Petras Dirgėla (born 1947), Lithuanian author
• Petras Geniušas (born 1961), Lithuanian classical pianist
• Petras Giniotas (born 1952), Lithuanian politician
• Petras Griškevičius (1924-1987), Lithuanian-Soviet politician
• Petras Kalpokas (1880–1945), Lithuanian painter and educator
• Petras Karla (1937–1969), Lithuanian rower and Olympic competitor
• Petras Klimas (1891–1969), Lithuanian diplomat, author and historian
• Petras Kubiliūnas (1894–1946), Lithuanian military officer and politician
• Petras Kunca (born 1942), Lithuanian violinist
• Petras Mantigirdaitis (died 1459), nobleman of the Grand Duchy of Lithuania and Grand Marshal of Lithuania
• Petras Jonaitis Mantigirdaitis (died c.1497), nobleman of the Grand Duchy of Lithuania
• Petras Poškus (born 1935), Lithuanian politician
• Petras Raslanas (born 1914), Lithuanian communist activist, politician and fugitive
• Petras Repšys (born 1940) Lithuanian artist
• Petras Rimša (1881–1961), Lithuanian sculptor
• Petras Šiurskas (born 1953), Lithuanian sprint canoer
• Petras Stankeras (born 1948), Lithuanian historian
• Petras Vaitiekūnas (born 1953), Lithuanian politician, former Foreign Minister of Lithuania
• Petras Vileišis (1851–1926), Lithuanian engineer, political activist and philanthropist

• Petras (surname)