Pollution management of water source is a guarantee for the safety of urban drinking water. In this study, the pollution status of the upstream of Laoshan Reservoir was quantitatively assessed in three aspects, including domestic pollution, poultry and livestock pollution, and agricultural non-point pollution. According to the field investigation data of the environment pollution, the pollutants loading and pollutants capacity of Laoshan Reservoir were also quantified. Finally, several countermeasures were proposed for improving the water quality of Laoshan Reservoir. This study may provide support for pollution control of Laoshan Reservoir and similar areas.