Watch shower whose size can be automatically regulated

The present invention relates to a telescopic watch carriage, its base seat is directly connected with lower watch support and an elastic component is set up between upper watch support and lower watch support. Said elastic component possesses an elliptical or polygonal hollow column body, top end of the hollow column body possesses a guide hole, and its internal cavity is equipped with a spring set against a piston fixedly connected with a slide bar, the slide bar is fixed on the upper watch support. Said slide bar is one with two cylindrical or polygonal bars or one with convex key. Said watch base seat can be automatically regulated in its length so that it is suitable for mounting watch with watchband of different length. Its structure is simple and compact, moulding is beautiful and cost is low.