Some 8,943 second-hand homes were sold in Beijing last month, the lowest number for any March since 2009, according to new data from property agent Centaline.
Zhang Dawei, chief analyst with Centaline, attributed the slump to tightening credit and increasing supplies of affordable housing.
Last month, the average price of second-hand homes came in at 31,400 yuan per square meter in the city, down 0.6 percent from February, the agent said.
Beijing promised to offer 20,000 units of a certain type of affordable housing in 2013, and 50,000 in 2014 to make homes more accessible to families crowded out of the expensive market.
The city has set specific requirements for families applying for the program and the management of the houses in order to prevent speculative investment.
Across the country, China's red-hot property market has been showing signs of cooling down in recent months. Home prices in major Chinese cities grew at a slower pace in February, with fewer cities seeing month-on-month price rises, according to official data.