Seoul shares turn flat amid caution, Samsung Elec firm
* Market's key heavyweights firm, Samsung Elec up for a 2nd day
* Insurers, airlines ease, Daewoo Shipbuilding rises on new order
* Foreign investors sell for a 6th straight session
SEOUL, July 10 (Reuters) - Seoul shares pared opening gains and turned flat on Wednesday as investors moved more cautiously before key Chinese economic data and major South Korean earnings in coming weeks, with foreign investors selling for a sixth straight session.
Investors will remain reluctant to actively make bets ahead of key Chinese economic data and major domestic earnings news in coming days and weeks, said Ko Seung-hee, a market analyst at SK Securities.
China's money supply and loan growth second quarter GDP data, monthly urban investment, industrial output and retail sales figures are due on or before July 15.
"Despite extremely attractive valuations, foreign investors are reluctant to get in. Strength in U.S. dollar this year played a part, as did general avoidance of emerging market assets," said Park Jung-seop, a market analyst at Daishin Securities.
Foreign investors were sellers of a net 17 billion Korean won ($14.89 million) worth of stocks, poised to offload shares for a sixth straight session.
The Korea Composite Stock Price Index (KOSPI) was down 0.05 percent at 1,829.48 points as of 0145 GMT, erasing earlier as much as 0.4 percent gain. The main KOSPI was also trading significantly below its 120-day moving average of around 1,950 points.
Samsung Electronics Co Ltd, biggest component on the main KOSPI, advanced 0.6 percent rising for a second session after posting sharp falls last week on second quarter earnings estimates below market consensus.
Gains in other large-cap stocks supported the market as Hyundai Motor Co, the second-biggest share on the KOSPI, gained 1.2 percent and POSCO advanced 0.7 percent.
Daewoo Shipbuilding & Marine Engineering Co Ltd shares rose 0.7 percent after the company said late on Tuesday it has won an order worth 481.2 billion won to build three container ships.
But insurers broadly eased as appetite for the sector chilled amid concerns over their potential exposure to Asiana Airlines Inc.
The South Korean airliner's Boeing 777 crash-landed in San Francisco on Saturday with more than 300 passengers on board.
Shares in Korean Reinsurance Co was down 0.5 percent and Samsung Fire & Marine Insurance Co Ltd declined 1 percent.
Both Asiana Airlines and Korean Air Line Co Ltd were down 0.8 percent on worries demand for South Korean airline flights may be affected by the San Francisco incident.
The KOSPI 200 benchmark of core stocks was up 0.03 percent, while the junior KOSDAQ edged 0.44 percent higher.
($1 = 1141.7000 Korean won) (Reporting by Jungyoun Park; Editing by Eric Meijer)