AbstracWater is a natural resource that is needed for the livelihood of many people and even by all living things. Therefore, water sources must be protected so that they can be utilized properly by humans and other living things. Waste management by an industry that is not done properly will affect the quality of the surrounding water resources. For example, water pollution that occurred in Retok Village, Kuala Mandor B District, Kubu Raya Regency, Terok river water was contaminated with palm oil industry liquid waste, which is suspected of having a leak in the PT SMS (Satria Multi Sukses) palm oil mill waste storage pond located upstream of the river. before there was pollution of the river, it was seen that the water was clear, there were still lots of fish, and the people used the water of the Retok river as a bathing place and a place to catch fish.River pollution as a result of oil palm processing business activities, water pollution has not been fully implemented, especially in the palm oil processing business in Retok Village, Kuala Mandor B District, Kubu Raya Regency. The oil palm processing business in Retok Village, Kuala Mandor B District, Kubu Raya Regency, is still being monitored by the local government (Environmental Service). Keywords: River Pollution, Monitoring, Law Enforcement. Abstrak Air merupaka sumber daya alam yang diperlukan untuk hajat hidup orang banyak bahkan oleh semua makhuluk hidup. Oleh karnena itu sumber air harus dilindungi agar tetap dapat dimanfaatkan dengan baik oleh manusia serta makhluk hidup lainnya. Pengelolaan limbah oleh suatu industry yang tidak dilakukan dengan benar akan berpengaruh terhadap kualitas sumber daya air yang ada disekitarnya. Seperti pencemaran air yang terjadi Di Desa Retok Kecamatan Kuala Mandor B Kabupaten Kubu Raya , air sungai terok tercemar limbah cair industi kelapa sawit yang diduga ada kebocoran kolam penampungan limbah pabrik sawit PT SMS (Satria Multi Sukses) yang terletak dihulu sungai. sebelum ada pencemaran sungai ,terlihat bahwa air jernih ,ikan masih banyak, dan masyarakat memanfaatkan air sungai retok sebagai tempat pemandian dan tempat mencari ikan.Pencemaran sungai akibat dari kegiatan usaha pengolahan kelapa sawit pencemaran air belum seutuhnya terimplentasi terutama terhadap usaha pengolahankelapa sawit yang ada di Desa Retok Kecamatan Kuala Mandor B Kabupaten Kubu Raya.berdasarkan penelitian di lapangan, usaha pengolahan kelapa sawit ini masih melakukan aktivitas seperti biasa dengan membuka usaha nya kembali dan perusahan tersebut masih dalam pantauan pemerintah daerah(Dinas Lingkungan Hidup) usaha pengolahan kelapa sawit di Desa Retok Kecamatan Kuala Mandor B Kabupaten Kubu Raya. Kata Kunci : Pencemaran Sungai, Pengawasan, Penegakan Hukum.