Mesothelioma is an aggressive tumor arising from the mesothelium, and is usually associated with previous exposure to asbestos. The incubation period of asbestos-related mesothelioma is estimated to be approximately 30-40 years. Once mesothelioma has occurred, there is no effective treatment. So, identification of tumor markers and a method for early diagnosis using such markers are urgently needed. Recently, several enzyme-linked immunosorbent assay systems for Erc/mesothelin have been developed, the reported usefulness of which has been assessed and demonstrated as a diagnostic tool. Asbestos-related mesothelioma should be ascribed as a typical environmental carcinogen. In this review, we will present asbestos-related mesothelioma for the study of problems in environmental carcinogenesis.