* HSI +0.1 pct, H-shares -0.3 pct, CSI300 +0.2 pct
* Units of state firms selected for reform moves rise
* Huadian Power jumps on positive profit alert
* China Shenhua down to 7-week low after coal price-cut (Updates to midday)
By Grace Li
HONG KONG, July 16 (Reuters) - Hong Kong and China shares eked out slim gains by midday on Wednesday, after China reported that second-quarter economic growth was slightly faster than market expectations.
China's economy expanded by 2.0 percent in the second quarter from the previous quarter, taking annual growth for April-June to 7.5 percent. Retail sales and industrial output were either in line with market forecasts or a bit higher.
At midday, the Hang Seng Index was 0.1 percent higher at 23,479.79 points. The China Enterprises Index of the top Chinese listings in Hong Kong fell 0.3 percent.
The CSI300 of the leading Shanghai and Shenzhen A-share listings rose 0.2 percent, while the Shanghai Composite Index inched up 0.1 percent to a one-month high at 2,071.90 points.
If gains hold, this could be the fourth straight winning session for both Chinese onshore indexes.
"The good data lent support to the expectation that China's economy will continue to stabilise in the second half, which could help the indexes to stabilise too," said Xiao Shijun, analyst at Guodu Securities in Beijing.
However, Xiao added that the rebound's momentum would be limited by concerns over new initial public offerings (IPOs) and interim results of overvalued growth companies.
The China Securities Regulatory Commission said late Monday it had given final approval to 12 firms seeking to list on the Shanghai or Shenzhen stock exchanges. The 10 IPOs that the commission approved in June were heavily subscribed.
A Securities Daily report on Wednesday said the new batch of IPOs is expected to lock up 766.5 billion yuan ($123.46 billion) in funds.
Shares of listed units of state-owned firms that Beijing had named in a statement on reform plans rose on Wednesday.
Tuesday's announcement named six state enterprises it said would participate in a reform process that could widen the role that private capital plays in China's massive state sector.
China National Building Material climbed 3.3 percent to its highest in three months. China Agri-Industries Holdings, a subsidiary of China National Cereals, Oils and Foodstuffs Corp (COFCO), rose 2.7 percent to a 5-month high. Both had accumulated gains earlier this week.
Three other COFCO affiliates jumped the maximum limit 10 percent on mainland bourses.
Huadian Power International Corp surged 11.4 percent in Hong Kong, its biggest jump in more than five years, and 7.5 percent in Shanghai. The power producer said late on Tuesday it expected first half net profit to be up about 55 to 65 percent.
China Shenhua Energy led losses on the Hang Seng for a second day, off 2.6 percent to the lowest since May 27. Shanghai Securities News reported on Wednesday the mainland's biggest coal producer again cut its steam coal prices.
$1 = 6.2086 Chinese Yuan Editing by Richard Borsuk