* CSI300 +0.8 pct; SSEC +0.8 pct; HSI +0.4 pct
* China shares on track for longest winning streak in 2 months
* Property shares rise on signs of market stabilization
SHANGHAI, Feb 17 (Reuters) - China shares rose to three-week highs on Tuesday, lead by gains in property firms after data showed some signs housing prices were starting to stabilise in the biggest cities.
Average new home prices in China's 70 major cities fell 0.4 percent in January from December, a ninth straight monthly drop, but price falls in Beijing and Shanghai eased, causing some speculation they may be bottoming out.
"During the fourth quarter, we saw an increase in trading volume as more people entered the property market after the government loosened policies," said Joe Zhou, analyst for property consultancy Jones Lang LaSalle in Shanghai. "We expect this trend to continue."
The CSI300 index rose 0.8 percent, to 3,528.79 points at the end of the morning session, while the Shanghai Composite Index gained 0.8 percent, to 3,248.82 points.
If the indices remain up, Tuesday will be their seventh straight advance and make the longest winning streak in two months. The streak has been supported by expectations of further policy easing to counter China's slowing economy.
Mainland markets will be closed from Feb. 18 through Feb. 24 for the Lunar New Year holiday.
The Hang Seng index added 0.4 percent, to 24,820.38 points. Hong Kong markets will open for a half-day on Wednesday, then be closed until Monday, Feb. 23.
On Tuesday, CSI300's property sub index was up 1.4 percent.
China's makers of electric cars and batteries surged on news of fresh policies to support sales of new-energy vehicles, while state-owned enterprises (SOE) in Shanghai broadly rose on signs of accelerated restructuring.
Shares of Chinese electric carmaker BYD Co Ltd surged their maximum 10 percent after the Ministry of Science and Technology said new policies would help the number of new energy vehicles in China hit 500,000 in the next five years.
Battery makers, which would benefit from a boom in electric vehicle sales, also surged. Shares of Sichuan Tianqi Lithium Industries Inc jumped 10 percent.
Four Shanghai-based state-owned companies, including Bright Dairy & Food Co Ltd and Shanghai Jinfeng Wine Co Ltd announced share ownership restructuring plans, fuelling expectations of similar reforms at other companies.
New A-share account openings bit.ly/1wvJ9S9
China trading volumes hit records in 2014 link.reuters.com/vag73w
Reporting by Samuel Shen and Kazunori Takada; Editing by Richard Borsuk