Adult somatic antigen extract of Paragonimus heterotremus was compared with excretory-secretory (ES) antigen in an enzyme-linked immunosorbent assay (ELISA) for serodiagnosis of human paragonimiasis. The absorbence values in ELISA using the adult somatic antigen were not significantly different from the values obtained using ES antigens ( P>0·05). The sensitivity of the ELISA using either antigen was 100%, but the specificity was 96% with somatic and 98% with ES antigens due to a cross reaction with fascioliasis sera. It appears that both somatic and ES antigens are effective antigens for use in serodiagnosis of human paragonimiasis heterotremus.