TAIPEI, Aug 6 (Reuters) - Taiwan stocks retreated from early strong gains on Tuesday morning amid lingering concerns over the outlook for the U.S. economy and tech companies following a record plunge a day earlier.

The main index jumped more than 4% in early trade to as high as 20,640.44 points, but quickly pared those gains to be up around 1%.

Shares in the dominant technology stock TSMC, the world's largest contract chipmaker, rose more than 6% in early trade before pulling back to a gain of around 4%.

Taiwan's other major-weighted tech stocks also rebounded. Mediatek was up 7.5% while Quanta rose 2.1%.

Taiwan was one of several markets that tumbled on Monday amid fears the United States could be heading for recession and as investors sought refuge from riskier assets.

Taiwan Stock Exchange President Lih-Chung Chien has said the bourse would work with regulators to maintain stability when needed. (Reporting by Faith Hung and Yimou Lee; Editing by Jacqueline Wong, James Pomfret and Sonali Paul)