Sperm examination is an important tool in estimating the fertilizing capacity of an ejaculate. The number of spermatozoa in a semen dose, morphology and motility are important for the fertilization process. By evaluation of semen, artificial insemination (AI) using high quality of semen can increase fertilization rate. Boar semen is subject to contamination by various pathogens that can result in fertility disorders in sows. Among these pathogens, porcine reproductive and respiratory syndrome virus (PRRSV), porcine parvovirus (PPV), porcine circovirus-2 (PCV-2) are of particular importance and accurate monitoring prior to and during the presence of boars in AI stations is essential. Because of the high risk of dissemination of disease via AI, The absolute goal is to provide pathogen-free semen and this is feasible with the adequate measures. The disease affects boars semen causes a significant reduction quality. In this study we investigated the characterization boar semen in Jeju, interaction of pathogenic virus infection with characterization of boar semen. Forty-two boar semen from 13 farms were investigated. The semen were stored during 5 days at 17℃ and the sperm qualities in the stored semen were analysed. Visual-motility assessment is a tool (Computer- Assisted Semen Analysis) used to determine the quality of boar semen. Percentage of morphologically normal spermatozoa were assessed. PRRS ,PPV and PCV-2 were detected in boar semen using PCR. The motion characteristics in boar semen was showed 68.4±9.1% for motility, 48.6±7.1 μm/s for VAP, 45.3±7.0 μm/s for VSL, 79.1±8.7 μm/s for VCL, 1.3±0.2 μm/s for ALH, 8.3±0.4 Hz for BCF, 93.6±3.5% for STR, 57.9±6.4 % for LIN. The percentage of sperm with abnormal head, midepeice and tail were 0.3±0.7%, 14.4±12.5%, 4.9±6.6%, respectively. Based on the PCR method, PPV was detected in 20 samples (48%). However, PCV-2 and PRRSV were not detected in any cases. Marked differences in motility and morphology between PPV negative and PPV positive semen were not observed. Sperm cell production was not affected by PPV infection. However, slight increases in detached head, coiled tail after infection were observed (p<0.05). The motility of semen in Jeju is similar to case comparing with other regions in Korea. Although PPV in semen was not affected in semen quality, there is the high risk of virus excretion in the semen of Jeju boars. Therefore continuous screening tests for some particular pathogens in boar semen would be warranted.