The invention discloses an antibacterial PPR (polypropylene random copolymer) water supply pipe of high low-temperature toughness, made from, by weight, 80 to 100 parts of PPR, 20 to 30 parts of polyisocyanurate, 15 to 25 parts of PA66 (polyamide 66), 3 to 10 parts of antioxidant, 2 to 8 parts of light stabilizer, 5 to 15 parts of organic antibacterial agent, 1 to 5 parts of dispersant, 4 to 8 parts of color masterbatch, and 1 to 5 parts of clay nano-composite. The antioxidant is one of 2, 6-tert-butyl-4-methylphenol and distearyl thiodipropionate. The light stabilizer is a combination of light stabilizer LQ-292 and light stabilizer 765 in any proportion. The organic antibacterial agent is one of vanillin and ethyl vanillin. The dispersant is vinyl distearamide. The clay nano-composite is phyllosilicate nano-material. The antibacterial PPR water supply pipe has excellent low-temperature toughness, oxidation resistance and light stability, is high in strength, can inhibit and kill germs in the pipe, is safe and environment friendly and high in cost performance and has promising market prospect.