* CSI300 +0.6 pct; SSEC +0.7 pct; HSI -1.3 pct
* Investors lukewarm to accelerated SOE reforms
* China's PMI survey on Wednesday in spotlight
SHANGHAI, Sept 21 (Reuters) - China stocks rose on Monday morning supported by demand for small caps while Hong Kong shares fell, with investor sentiment soured by weakness in global equity markets.
China's key indexes opened lower but edged up by the lunch break. The CSI300 index rose 0.6 percent, to 3,271.26 points, while the Shanghai Composite Index gained 0.7 percent, to 3,118.81 points.
Small-caps rebounded strongly, with Shenzhen's start-up board ChiNext up 3 percent, and an index tracking tech shares surging 3.2 percent.
"Investors seem to be favouring short-term trading in the IT sector with relatively frequent rallies and corrections," wrote Gerry Alfonso, director at Shenwan Hongyuan Securities.
But trading remained thin, with the market still in a downtrend and many traders staying sidelined amid lingering worries about the economy.
Markets are looking to China's flash factory activity survey on Wednesday for clues on whether the economy is deteriorating more rapidly than earlier thought.
A Reuters poll showed economists expect the flash September China factory PMI headline reading to edge up to 47.5 from 47.1 in August. But it likely remained near 6/1-2-year lows, pointing to a seventh straight contraction in activity on a monthly basis.
"A below 50 print will reinforce expectations for GDP growth to slow to 6.4 percent in Q3," ANZ said in a research note.
Blue chips, mostly state-owned, had a mixed performance as investors gave a lukewarm response to accelerated reforms for the bloated state sector.
China's top economic planner has vowed to implement "mixed ownership" reforms in sectors such as electricity, oil, rail and airlines, as part of Beijing's overhaul of its inefficient state-owned enterprises (SOEs).
"SOE reform remains a confusion given the apparent contrasts between those pushing market-oriented reform and mixed ownership, and those stressing the role of the Communist Party," said Oliver Barron, analyst at China-focused investment bank NSBO.
Transportation and energy shares rose, but banking stocks were lower by midday.
Hong Kong stocks fell in morning trading, along with major markets in the region.
The Hang Seng index dropped 1.3 percent, to 21,635.13 points, while the Hong Kong China Enterprises Index lost 2.1 percent, to 9,821.84.
U.S. and European stocks closed lower on Friday as the Federal Reserve's decision to keep interest rates near zero fuelled concerns about the potential impact of continuing weak global growth.
Shanghai Jin Jiang International Hotels Group fell 3.3 percent, after it agreed to acquire an 81 pct interest in Keystone Lodging Holdings for a consideration of 8.27 billion yuan ($1.30 billion). Analysts said the deal was expensive.
$1 = 6.3671 Chinese yuan Reporting by Samuel Shan and Pete Sweeney; Editing by Jacqueline Wong