The invention discloses an auxiliary transfer pump station of drainage tunnel in subway crossing. The auxiliary transfer pump station of drainage tunnel in subway crossing includes an upstream drain, an upstream flume, a diversion partition, a rack, a regulating gate, a stilling basin, a partition hole, a collecting basin, a wet-pit pump, a maintenance platform, an overflow tank, a downstream drain, a pressure drain pump, a pump interlayer, a sewage pump floor, an equipment transport channel, a pump lifting hole, a control board, a control cabinet, a manhole, a hole for hoist and a pump room. The auxiliary transfer pump station of drainage tunnel in subway crossing aims at features of an outlet tunnel in subway crossing, which are that displacement is larger, interval is long and embedded depth is deep. The auxiliary transfer pump makes combination of a drainage pumping station and a transfer pumping station come true. The auxiliary transfer pump station of drainage tunnel in subway crossing has many advantages, for example, water pump can be stopped when maintenance is needed, degree of automation is high, civil investment and construction difficulty can be diminished and safety and reliability of operating drainage can be improved.