Imports of Russian oil, including supplies pumped via the East Siberia Pacific Ocean pipeline and seaborne shipments from Russia's European and Far Eastern ports, totalled 8.342 million tonnes, data from the Chinese General Administration of Customs showed.
The August amount, equivalent to 1.96 million barrels per day (bpd), was slightly off May's record of nearly 2 million bpd.
read moreStill, imports from Saudi Arabia rebounded last month to 8.475 million tonnes, or 1.99 million bpd, 5% above the year ago levels.
China's crude oil imports in August fell 9.4% from a year earlier, as outages at state-run refineries and lower operations at independent plants caused by weak margins capped buying.
The strong Russian purchases continued to weigh on competing supplies from Angola and Brazil, which fell in August by 34% and 47% year-on-year, respectively.