The benchmark weighted-average seven-day bond repurchase rate fell 4.14 basis points to 3.3320 percent from 3.3734 percent at the close on Friday.
The 14-day repo rate rose to 3.3964 percent from 3.3775 percent, and the shortest overnight one-day repo rate inched up to 2.7025 percent from 2.6609 percent.
"The money situation is still good and the impact of the reserve requirement ratio payments is not large," said a dealer at a Chinese commercial bank in Shanghai. "We are paying more attention on the amounts of central bank's reverse repos."
This week, maturing bills, repos, and reverse repos will drain a net 523 billion yuan from the banking system, which will be offset by any injections conducted by the central bank this week.
Last week, the People's Bank of China conducted a net injection of 379 billion yuan ($60.74 billion) into the banking system, the biggest injection since Reuters' records began.
Traders said rates may fall further by the middle of next week, when banks complete their reserve payments.