The editorial board at The Post should have checked its facts before panning Democratic candidate Richard Gephardt's campaign commercials regarding foreign trade barriers {editorial, Feb. 10}. While I am not a particularly big fan of Mr. Gephardt's proposed trade policies, there can be little debate that Korean trade practices discriminate against U.S. autos.

The Post seems to be saying that it's all right for a $10,000 Chrysler K-car to cost $29,000 in Korea because "eight of the nine {Korean} surcharges are also imposed on cars produced in South Korea." In The Post's view, the Korean government's policies are simply intended to dampen domestic consumption of all automobiles, rather than discriminate against U.S. autos, as Mr. Gephardt alleges.

The Post is wrong. Up until July 1, 1987, the Korean government had an outright prohibition against the importation of any foreign car, according to the American Chamber of Commerce in Korea. Even today U.S. autos face a total import penalty of over 108 percent as they attempt to compete with Korean cars of similar value. For example, the Korean government imposes a 15.2 percent value-added tax on domestically produced autos; the value-added tax for foreign autos such as the K-car is a hefty 25.9 percent. Similarly, the "defense tax" charges by Korea on foreign autos is almost twice that imposed on domestically produced cars. Korean automobile makers pay only a 5.8 percent U.S. duty on their exports to us.

A final point: U.S. automakers are not allowed to directly distribute their products in the Korean market. Instead, our cars must be sold through Korean middlemen. No American automaker trying to sell cars in Korea is ever allowed to set up the same distribution network that a company such as Hyundai is allowed to set up in the United States practically overnight.

It is wrong for Mr. Gephardt's commercials to suggest that America's trade woes are caused solely by unscrupulous foreigners; however, it is clear that part of the problem comes as a result of unfair foreign trade barriers.

DANIEL J. JOURDAN Arlington

The writer is a legislative assistant to Rep. Sander Levin (D-Mich.) specializing in commerce.