The present invention provides a water spot cooling device of a bottom mold for wheel hub casting, a method for cooling a bottom mold by using the device, and a method for manufacturing the device. The device and the method of the present invention have the advantages that multi-path spot cooling required by spoke cooling is integrated into one device; the influence of backwater on the mold is eliminated and stable production is benefited; the effluent water from the multi-path spot cooling is gathered to one backwater opening through a backwater crossing and a backwater annular passage, thereby simplifying a backwater device and making the pipeline connection of the device simpler; and there is no special part in the whole device so that the machining cost is reduced and the maintenance is more convenient.