The invention provides a telescopic rain shed, which comprises support frames, a slide frame and a slide device. The support frames are provided with rain sheds, a gear face is arranged on one inner lateral side of one support frame, the rain sheds are arranged above the slide frame, and groove holes are arranged on the lateral sides of the slide frame opposite to the gear face arranged on the support frames. The slide device comprises a guide rod, a fixed frame, a twisting rod, a first transmission wheel and a gear, wherein the first transmission wheel is fixedly sleeved on the guide rod, the gear is fixedly sleeved at the tail end of the guide rod, the gear is meshed with the gear face arranged on the support frames through the groove holes, a wrench is arranged at the tail end of the twisting rod, a second transmission wheel is fixed at the other tail end of the twisting rod, and the second transmission wheel is matched with and abuts against the first transmission wheel. The telescopic rain shed is attractive and convenient. Due to the facts that the rain sheds are made of steel plates or plasticizing glass and the structure of the telescopic rain shed adopts steel, the telescopic rain shed is firm and durable.