<p>A backflow preventer used in bath field comprises a base (100) and an elastic sealing element (200). The base (100) is provided with a waterway (140), a fixing seat (120) arranged in the waterway (140) and at least one spoke (130) for fixedly connecting the fixing seat (120) in the waterway (140). A passage is formed between the spokes (130). The elastic sealing element (200) is provided with an elastic sealing sheet (210) and a fixing portion (220) arranged on the front of the elastic sealing sheet (210). The fixing portion (220) is fixedly connected to the fixing seat (120). The elastic sealing piece (210) matches with the waterway (140), wherein the elastic sealing sheet (210) opens the passage under a forward flow impact action if the flow in the waterway (140) is forward; the elastic sealing sheet (210) closes the passage under a backflow impact action if the flow in the waterway (140) is backward. The backflow preventer is adapted to be used in a shower or a tap in bath field and has advantages of high practicality, few components and low cost.</p>
