160 clinical samples were collected from 40 infertile couples with unexplained infertility. The samples collected included serum and seminal plasma of the male partners and serum and cervical mucus samples of the female partners. 25 fertile healthy couples were investigated as controls. All the samples collected were then tested for class-specific antisperm antibodies by an Enzyme linked immunosorbent assay (ELISA). Antisperm antibodies were detected in 30% of the infertile couples which included 25% female and 10% male partners. Amongst the cases positive for antisperm antibodies, antibodies were detected most frequently in female sera 58.4% followed by male sera 33% and 25% in cervical mucus. The isotyping of antisperm antibodies in various samples showed IgG to be the most frequent type specific antibody followed by IgM & IgA types of antibodies. ELISA has provided a relatively simple, reliable and highly reproducible method of detection of antisperm antibodies. Thus application of antisperm antibody testing especially in cervical mucus should become an integral part of the investigation of immunologic infertility.