The company, known formally as Petroleo Brasileiro, said Wednesday it sold its shares, owned by subsidiary Petrobras Energia Peru, to CNPC.
"The assets that comprise the transaction are: 100 percent stake in Block X, which is a mature field in operation since 1912, with production in 2012 of 16,000 barrels of oil equivalent per day; 46.16 percent interest in Block 57, pre-operational natural gas and condensate field; and 100 percent interest in Block 58, exploratory block neighbor to Block 57 where recent significant discoveries of natural gas and condensate have been made," the company said.
PetroChina, a division of CNPC, said in a separate statement the remaining stake in Block 57 is owned by Spanish energy company Repsol.
PetroChina said the three blocks in Peru have "sizable recoverable reserves." It listed the current production rate at 800,000 tons of oil equivalent per year.