Pollutants are regarded as a harmful substance when it is discharged into the environment; it enters the water environment and affects the environment's physical, chemical, and biological properties. Non-point source comes from various sources that its pollutant will enter the water body, stream bank in directly. Best management practice is an important measure for watershed non-point source pollution control and its goal is to minimize pollution reduction in basin. This chapter helps people to understand about non-point source pollution, best management practice, and control for non-point source pollution via the best management practices. Furthermore, this chapter are proposed the best management practices to reduce nutrients and control non-point source pollution as using bio-pretention method via pond and vegetated buffer or vegetated swale in agricultural runoff; riparian buffer restoration or storm drain channel to reduce runoff velocity before conducting to be filter in storming condition of agricultural runoff; using vegetated filter under roof or strip form with urban runoff; sediment restoration or vegetated roof to reduce quickly sediments, then using wetland stores to keep nutrients from non-point source pollution in building runoff; using soil amendment and restoration as well as dry well to keep big amount of grease in oil/grease runoff; using vegetated strips or roof, wetland channel, especially grassy buffer in road runoff; and natural wetland, wetland banks, and vegetated buffers in forest runoff.