On Tuesday, the People's Bank of China (PBoC) poured 440 billion yuan (USD 67 billion) into the system through regular open market operations, which Bloomberg News said was the biggest in three years.
Chinese companies typically pay salaries and bonuses before the holiday, which falls in early February this year. People also traditionally exchange cash and gifts during the period.
The PBoC last week flooded the financial system with more than 1.5 trillion yuan.
China's economy grew at its slowest rate in a quarter of a century in 2015, at 6.9 per cent, raising expectations for further cuts in interest rates or reserve requirements.
"The huge amount of open-market injections are targeting the pre-holiday cash demand," Liu Changjiang, a Shanghai-based bond analyst at Soochow Securities, told Bloomberg.