ABSTRACT: This study analyzed the trend in semen quality of infertile male patients in Wenzhou, China, based on the data obtained from 38 905 patients during 2008-2016 in The First Affiliated Hospital of Wenzhou Medical University (Wenzhou, China). The results showed that only 24.9% of the patients had normal semen quality. For the semen quality of infertile male patients, that of the workers and 40-year-olds was significantly worse than the other occupational and age groups. For all the infertile patients, low semen volume, asthenozoospermia, and teratozoospermia accounted for 8.4%, 50.5%, and 54.1%, respectively. During 2008-2016, the annual mean percentage of fast forward motile spermatozoa, percentage of total forward motile spermatozoa, and percentage of spermatozoa with normal morphology decreased linearly with slopes of -2.11, -2.59, and -0.70, respectively. The proportion of patients with asthenozoospermia and multi-abnormal spermatozoa increased during 2008-2016 with slopes of 4.70 and 4.87, respectively, while for low semen volume, it decreased with a slope of -0.47 in the same time period. The proportion of patients with teratozoospermia increased from 2008 to 2011 and from 2011 to 2016 with slopes of 17.10 and 2.09, respectively. In general, the deteriorating trend of semen quality of infertile male patients in Wenzhou was obvious. Future efforts should be made to reveal the adverse influences on semen quality, such as occupational exposure, environmental quality, and living habits. Furthermore, more pervasive reproduction health education is necessary.