Underground garage drainage system

The utility model discloses an underground garage drainage system which comprises a garage bottom plate and a garage surface layer laid above the garage bottom plate, a drainage plate for isolating the garage bottom plate from the garage surface layer is arranged between the garage bottom plate and the garage surface layer, and the drainage plate is fixed on the garage bottom plate through hot melting welding. The multiple garage bottom plates and the multiple garage surface layers are arranged at intervals, and water collecting pits are formed by gaps between the adjacent garage bottom plates. According to the underground garage drainage system, the drainage plate with the bosses is arranged between the garage bottom plate and the garage surface layer, water seepage from the garage bottom plate to the garage surface layer is cut off, concrete is poured into boiling points of the drainage plate to form supporting legs, confluence channels are formed between the protruding points, and water is poured into a wa