China's central bank on Friday pumped 20 billion yuan ($3 billion) into the market to preserve liquidity.
The People's Bank of China (PBOC) put 50 billion yuan into seven-day reverse repos priced to yield 2.25%, Xinhua news agency reported.
Reverse repos worth 30 billion yuan mature on Friday, so the central bank has effectively injected 20 billion yuan into the market.
On Friday's interbank market, the benchmark overnight Shanghai Interbank Offered Rate (Shibor) was down by 0.2 basis point to 2.008%.
Seven-day Shibor stayed unchanged at 2.331%. Three-month Shibor rose 0.15 basis point to 2.9288%.
The PBOC has pumped a net total of 50 billion yuan into the market this week, ending the consecutive currency withdrawal of the previous three weeks.