The purpose of this research was to determine the reproductive system and fish spawning season (Ompok hypophthalmus) in Pinang Luar and Pinang Dalam Lakes in Buluh Cina Village of Kampar. This research was conducted at Oxbow Lake of Buluh Cina Village and the Ecology Laboratory of the Faculty of Fisheries and Marine Sciences, University of Riau. Sampling collection of O. hypophthalmus was carried out at Oxbow Lake (Pinang Dalam and Pinang Luar Lakes) of Buluh Cina from September to November 2016. Meanwhile, measurement of in situ water quality and data retrieval was carried out only on September 14, 2016. O. hypophthalmus is estimated to experience spawning only once a year. Spawning time or spawning of fish in November in 2016 was estimated to be exactly the time after the full moon in November before December. Glass catfish studied was not related to the rainy season which usually occurs in the same fish in the Kampar river, because that year coincided with the summer in those months. In recent years, there has been a lot of talk about global climate change which causes uncertain environmental and seasonal conditions. Erratic seasonal conditions have caused the rainy and dry seasons to be erratic. Every living creature, including fish, is strongly influenced by its environmental parameters, whether in the form of the season or the environmental conditions of its own environmental parameters. Although this research was only carried out in a short period of time, it was necessary to look at the influence of the environment on fish that was focused on glass catfish (O. hypophthalmus) at Oxbow Lake of Buluh Cina Kampar Protected Forest.