The Chinese manufacturing PMI fell to 49.4 in January from 49.7 in December, according to the Chinese government on Monday. It was the lowest reading since August 2012.
Analysts had expected the index to decline to 49.6.
A reading above the 50 mark indicates expansion, a reading below 50 indicates contraction.
The services PMI decreased to 53.5 in January from 54.4 in December.