After new medical system of separation of dispensary from medical practice was started in 2000 in Korea, to expand bioequivalence-proven drug products and to ensure the credibility of the therapeutic equivalence of generic drugs are hot issues in Korea. It will be obligatory to submit bioequivalence reports for getting licenses of all generic prescription drugs in the near future. Like other countries such as US and Japan, the KFDA also has a plan to re-evaluate the already approved drugs by bioequivalence studies. Therefore, it becomes more necessary to develop bioequivalence-demonstrating methods for specific preparations such as topical drug products among already approved drug products. There are some differences between US and Japanese guidances of bioequivalence studies of generic drug products for topical use. The information on Japanese guidance and the guidance`s Q&As is already provided in our previous paper. In this paper. we examined the US guideline published in 1995 and compared with the Japanese guideline. which will give a useful information to make a guidance on bioequivalence studies of topical drug products in Korea.