Height adjusting system for supporting legs of child seat

The invention provides a child seat supporting leg height adjusting system which comprises a supporting leg height adjusting mechanism, the supporting leg height adjusting mechanism comprises a guide rail, a supporting leg, a worm gear, a worm and a driving part, the guide rail is vertically arranged on the rear portion of a base of a child seat, a T-shaped sliding groove is formed in the guide rail, and the supporting leg is arranged in the T-shaped sliding groove. The extending direction of the T-shaped sliding groove is the same as the extending direction of the guide rail. The supporting legs are arranged in the T-shaped sliding grooves in a sliding mode, bearing seats are vertically arranged at the upper ends and the lower ends of the supporting legs correspondingly, and the two ends of the worm are rotationally connected with the two bearing seats through bearings correspondingly; the worm gear is meshed with the worm, and the driving piece is used for driving the worm gear to rotate. Stepless adjustmen