* KOSPI falls, foreigners net sellers
* Korean won strengthens against U.S. dollar
* South Korea benchmark bond yield falls
* For the midday report, please click
SEOUL, May 21 (Reuters) - Round-up of South Korean financial markets:
** South Korean shares ended lower on Friday, as foreigners turned net sellers, erasing earlier gains led by technology shares and upbeat exports data. The won gained, while the benchmark bond yield fell.
** The KOSPI closed down 5.86 points, or 0.19%, at 3,156.42, after gaining as much as 1.13% in early trade.
** The benchmark index ended the week higher with a gain of 0.10%. It fell 1.37% in the previous week.
** Among technology heavyweights, chip giant Samsung Electronics rose 0.75%, while internet giant Naver and mobile messenger operator Kakao added 2.56% and 3.08%, respectively.
** Foreigners were net sellers of 135.3 billion won ($120.08 million) worth of shares on the main board.
** Data showed on Friday South Korean exports had surged 53.3% on-year during the first 20 days of May, helped by strong chip and car sales as well as higher demand from China and the United States.
** The won was quoted at 1,127 per dollar on the onshore settlement platform, 0.44% higher than its previous close at 1,132.0.
** On a weekly basis, it edged up 0.14%, after falling 0.65% a week earlier.
** In offshore trading, the won was quoted at 1,126.8 per dollar, up 0.1% from the previous day, while in non-deliverable forward trading its one-month contract was quoted at 1,126.3.
** In money and debt markets, June futures on three-year treasury bonds rose 0.06 points to 111.08.
** The most liquid three-year Korean treasury bond yield fell by 0.4 basis points to 1.099%, while the benchmark 10-year yield fell by 1.1 basis points to 2.124%. ($1 = 1,126.7500 won) (Reporting by Joori Roh; Editing by Arun Koyyur)