Crude oil output of major producers came in at 15.96 million tonnes, according to the National Bureau of Statistics.
Data given by the General Administration of Customs showed the country's imports in March reached 39.17 million tonnes.
In March, refineries processed 51.51 million tonnes of crude oil, up 8.3 percent year on year.
Meanwhile, China's natural gas output grew 0.4 percent year on year to 13.5 billion cubic meters in March, while imports of natural gas grew 38 percent year on year to reach 8.23 billion cubic meters.
China aims to increase annual domestic crude oil output to 200 million tonnes by 2020, while supply capacity for natural gas should exceed 360 billion cubic meters.