The purchasing managers' index (PMI) for China's non-manufacturing sector came in at 50.6 in September, down from 52.6 in August, the National Bureau of Statistics (NBS) said Friday.
A reading above 50 indicates expansion, while a reading below it reflects contraction.
The construction sector maintained brisk expansion in September, with the sub-index for business activities in the sector reaching 60.2, 3.7 percentage points higher than the August level, according to the NBS.
The service sector was weaker this month as the epidemic and other factors weighed on market activities. The sub-index for business activities declined 3 percentage points from last month to 48.9.
Friday's data also showed that the PMI for China's manufacturing sector came in at 50.1 in September, up from 49.4 in August.