Shanghai, July 6 (Reuters) - China stocks ended lower on Tuesday, with healthcare and tech firms leading the losses, as local investors remained wary of lofty valuations of certain sectors.

** The blue-chip CSI300 index edged down 0.1% to 5,083.10, while the Shanghai Composite Index ended flat at 3,530.26 points.

** Shenzhen's start-up board declined 1.8%, while Shanghai's tech-focused lost 2.7%.

** Leading the declines among sectors, the CSI300 healthcare index tumbled as much as 6% before ending 3.8% lower.

** Hangzhou Tigermed Consulting Co Ltd, Shanghai Fosun Pharmaceutical Group Co Ltd, Aier Eye Hospital Group Co Ltd , Beijing Tongrentang Co Ltd, and Wuxi AppTec Co Ltd retreated between 5% and 10.9%.

** "The growth rates of many healthcare firms could not support their current high valuations," Yan Kaiwen, an analyst with China Fortune Securities said.

** Yan said some investors shifted to cheaper sectors with stable growth, including developers.

** The CSI300 real-estate index climbed 2.9%, with bellwether Vanke up 2.8%.

** Around the region, MSCI's Asia ex-Japan stock index was firmer by 0.08%, while Japan's Nikkei index closed up 0.16%.

** At 0713 GMT, the yuan was quoted at 6.4612 per U.S. dollar, 0.04% firmer than the previous close of 6.4639.

** As of 0714 GMT, China's A-shares were trading at a premium of 39.50% over the Hong Kong-listed H-shares. (Reporting by Shanghai Newsroom, Editing by Sherry Jacob-Phillips)