The utility model discloses a bacteriostatic direct drinking water treatment device completely with no secondary pollution. The bacteriostatic direct drinking water treatment device comprises a pretreatment system, an advanced treatment assembly and an after-treatment system, which are communicated in sequence, wherein a water inlet of the pretreatment system is connected with a tap water inlet pipe, the after-treatment system comprises a rear-mounted active carbon filter and a water storage tank communicated with the rear-mounted active carbon filter, a water inlet of the rear-mounted active carbon filter is communicated with a water outlet of the advanced treatment assembly, a pipeline connecting the advanced treatment assembly with the rear-mounted active carbon filter and a pipeline connecting the rear-mounted active carbon filter with the water storage tank are respectively a titanium pipe, a shell of the rear-mounted active carbon filter is a titanium shell, the inner surface of the water storage tank is coated with a nano TiO2 film layer, a stirrer is installed in the water storage tank, a sterilizing lamp is installed on a stirring shaft of the stirrer, and the lower part of the water storage tank is connected with a direct drinking water outlet pipe. The bacteriostatic direct drinking water treatment device is reasonable in structure design and convenient to use, the secondary pollution of the drinking water can be completely prevented after the municipal tap water is treated by utilizing the device, and thus the water is healthy and safe to drink.