Background:Mumps is caused by a RNA virus belonging to the myxo virus group. One of its most notorious complications is mumps orchitis. Although it may cause infertility in some of the affected males, the exact mechanisms of fertility impairment are not entirely understood. Mumps viruses can attach to the sperm surface, and, serving as haptens, lead to the production of sperm antibodies. Aims and objectives: 1. To know if there is a relation between the infection by mumps after puberty and the result of seminal fluid analysis. 2. To determine the presence of anti-sperm antibodies(ASAs) in male serum and semen. 3. To know the relation between pumps in puberty and the ASAs in semen and serum of infertile males. Patients and methods:A cross sectional study carried in subfertility care and IVF centre in Erbil city in Iraqi Kurdistan from November 2013-September, 2014. 200 infertile males were included in the study. A semen specimen was collected and analysed for semen parameters, the seminal fluid analysis of semen was classified the seminal fluid to normal and abnormal according to WHO guideline. Serum and semen collected from males for detection of antisperm antibodies by using ElISA (enzyme linked munosorbent assay) used for detection ASAs in the serum of males and also for detection ASAs in male seminal fluid qualitatively. Result:The mean age of infertile male participated in the study was (33.905 year) with maximum and minimum age was (51year, 22 year) respectively, among 200 male the frequency of males with history of mumps after puberty was 26 which represents about 13% of infertile male whom participated in the study. Among 26(13%) of infertile males with history of mumps after puberty 16 infertile which represents about (61.54%) they have abnormal seminal fluid analysis. Anti-spermanti-bodies was positive in the serum of 12(46.15%) males out of 26 males with history of mumps after puberty and Anti sperm antibodies found in the semen of 18(54.55%) males with history of mumps infection after puberty. Conclusions:Mumps can cause infertility in male if they infected after puberty due to the rupture of testis blood barrier and can affect the sperms either by decreasing the count or motility so it can lead to oligozoospermia or asthenozoospermia, mumps also canlead to production of antibodies against sperm and can be detected either in blood or seminal fluid and these