Activity in China's services sector expanded at the fastest pace in three months in August as new orders rose, prompting the biggest increase in hiring in over a year, the survey showed.
Positive sentiment over the survey seeped into Southeast Asian markets with China being the region's biggest trading partner.
Singapore shares jumped 1.3%, shrugging off a central bank survey showing a sharp cut in 2019 economic growth forecasts.
Industrial and financial stocks were the top gainers, with industrial behemoth Jardine Matheson Holdings Ltd rising 5.6%, while Hongkong Land Holdings Ltd jumped 9.2%.
Thai stocks advanced 1% to a near one-month closing high after the finance minister played down recession fears.
The economy is just slowing but not in a recession yet and recently announced government stimulus measures should help lift growth to 3% this year, the minister said.
Index heavyweights Airports of Thailand and PTT PCL gained 3.5% and 1.8%, respectively.
Malaysian stocks gained 0.5% following a surprise rise in July exports.
Exports rose unexpectedly in July, rebounding from a drop in the previous month, lifted by solid demand for manufactured goods and higher shipments to China, government data showed. Financials were the top gainers, with Public bank Bhd rising 1%, while Malayan Banking Bhd added 0.5%.
Philippine shares climbed 0.5%, underpinned by real estate and industrial stocks.
Robinsons Land Corp and SM Investments Corp gained 4.1% and 3.8%, respectively.
Indonesian shares edged higher, aided by energy and real estate stocks, while Vietnam slipped on losses in consumer and industrial stocks.