The utility model relates to a siphon pipe assembly device for a solar heater. The device includes a water feeding and discharging pipe (1), a siphon main piece (2), a porous silica gel ring (3), a siphon pipe (4) and a silicone pipe (5), and is characterized in that the water feeding and discharging pipe (1) is arranged in the middle on one side of the siphon main piece (2); the water feeding and discharging pipe (1) is connected with a water tank of the solar heater; the porous silica gel ring (3) is arranged at the two ends of the siphon main piece (2); one end of the siphon pipe (4) is arranged on the porous silica gel ring (3); one end of the silicone pipe (5) is placed at the other end of the siphon pipe (4); and the other end of the silicone pipe (5) is placed in a vacuum pipe of the solar heater. The siphon pipe assembly device has simple structure, simplicity of mass production, installation, maintenance, popularization and application, and low cost, and can improve the heat efficiency of the ordinary household vacuum pipe solar heaters.