The invention discloses automatic downward-drilling drainage equipment. The equipment comprises an automatic downward-drilling drainage instrument, a guide line, a main extraction pipe, a pressure ventilation pipe, an electromagnetic three-way valve, a drilling extraction pipe, a drainage pipe, a check valve, a hole sealing material, an upper liquid level sensor and a lower liquid level sensor. The automatic downward-drilling drainage instrument comprises a flameproof enclosure, LED display lamps, a data transmission port and a control system, and the LED display lamps and the data transmission port are arranged on the flameproof enclosure. The control system is arranged in the flameproof enclosure and comprises a data processing module, a data transmission module, a power conversion module, a 458 communication module and a relay, the relay is electrically connected with the electromagnetic three-way valve, and the data transmission module is connected with the upper liquid level sensor and the lower liquid level sensor. The automatic downward-drilling drainage equipment is capable of automatically monitoring water quantity conditions in downward drilled holes, automatically draining according to water quantity and displaying drilled hole states through the LED lamps and uploading to a ground monitoring station to make it convenient for monitoring, and the requirement of informationized mine construction is met.