The official non-manufacturing purchasing managers' index rose from April's 54.8 to 55.5 in May, according to the National Bureau of Statistics. New orders reached an eight-month high of 52.7, up from April's 50.8.
However, the final reading of the HSBC/Markit manufacturing PMI for May came in at 49.4, up from 48.1 in April. This was weaker than the flash estimate of 49.7
The recent slew of Chinese data has reinforced hopes that the world's second largest economy may not be facing the severe slowdown that was predicted.
"It is the largest pick-up in the index since last August, which alongside the third successive pick-up in the official manufacturing PMI announced on Sunday, suggests that much of this downward pressure is being offset by warming foreign demand" said Julian Evans-Pritchard, China economist at Capital Economics.
The Nikkei was up on the back of comments by Bank of Japan (BoJ) governor Haruhiko Kuroda that the BoJ wouldn't hesitate to change policy to meet the two per cent inflation target.
The Reserve Bank of Australia has maintained its benchmark cash rate at 2.5 per cent. The Reserve Bank of India also held its previous stance.
Wall Street finished on a high after the release of positive manufacturing data.