A sprinkler includes a base, a positioning collar connected to the base, a gear box connected to the positioning collar and a sprinkling member which is co-rotated with the gear box, and a bypass tube connected between the positioning collar and the sprinkling member. The positioning collar is connected with a hose for introducing water to drive the gear box and the sprinkling member. A portion of the water from the hose enters the bypass tube and is introduced into the other end of the sprinkling tube. The water is introduced into the sprinkling tube from two positions to increase the volume of the water ejected from the sprinkling tube so as to cover a larger area.
