Overall sales in the world's biggest car market totaled 2.13 million vehicles in May, data from the China Association of Automobile Manufacturers (CAAM) showed.
China sold 10.88 million vehicles between January and May, up 36% from the same period a year earlier.
A global chip shortage and surging raw material prices are having an increasing impact on automakers in the country, said Chen Shihua, senior official at CAAM.
But Chen said CAAM remains cautiously positive about the sector's outlook. The industry body earlier expected China's overall vehicle sales to grow 6.5% this year.
Sales of new energy vehicles (NEVs), including battery-powered electric vehicles, plug-in petrol-electric hybrids and hydrogen fuel-cell vehicles, maintained their strong momentum, jumping 160%, with 217,000 units sold in the month.
NEV makers, such as Nio Inc, Xpeng Inc and BYD, are expanding manufacturing capacity in China, encouraged by the government's promotion of greener vehicles to cut pollution.
Tesla Inc sold 33,463 China-made electric cars in May.
Automakers including Honda Motor , Geely , and General Motors Co's China joint venture reported lower sales in May.
(Reporting by Yilei Sun and Tony Munroe; Editing by Clarence Fernandez and Kim Coghill)