* KOSPI rises for third straight session

* Korean won weakens against U.S. dollar

* South Korea benchmark bond yield drops

* For the midday report, please click

SEOUL, Aug 16 (Reuters) - Round-up of South Korean financial markets:

** South Korean shares extended their gaining streak to a third session on Tuesday to end at their highest in more than two months, as gains in heavyweight chipmakers offset the impact from economic slowdown concerns.

** The Korean won weakened, while the benchmark bond yield fell.

** The benchmark KOSPI ended up 5.58 points, or 0.22%, at 2,533.52, its highest close since June 10.

** Leading the market's strength were technology giant Samsung Electronics and peer SK Hynix, up 1.33% and 3.64%, respectively.

** But less than 50% KOSPI shares advanced of the total 929 that traded.

** Auto-parts maker Hyundai Mobis lost 3.53% as the affiliate of Hyundai Motor said it was considering reorganisation of business structure.

** China's central bank cut key lending rates in a surprise move on Monday to revive demand as data showed the economy unexpectedly slowing in July, with factory and retail activity squeezed by Beijing's zero-COVID policy and a property crisis.

** The market lost steam with weakening expectations for economic growth, said Huh Jae-hwan, analyst at Eugene Investment and Securities, who saw chipmakers' gains to be little more than technical adjustments.

** Foreigners were net buyers of 56.8 billion won ($43.40 million) worth of shares on the main board.

** The won was last quoted at 1,308.1 per dollar on the onshore settlement platform, 0.44% lower than its previous close at 1,302.4.

** In offshore trading, the won was quoted at 1,308.6 per dollar, up 0.1% from the previous day, while in non-deliverable forward trading its one-month contract was quoted at 1,307.7.

** In money and debt markets, September futures on three-year treasury bonds jumped 0.33 point to 105.42 in late afternoon trade.

** The most liquid 3-year Korean treasury bond yield fell by 10.3 basis points to 3.087%, while the benchmark 10-year yield dropped by 13.8 basis points to 3.165%. ($1 = 1,308.7300 won) (Reporting by Jihoon Lee; Editing by Vinay Dwivedi)