A heat supply network gateway station system utilizing dead steam of a thermal power plant steam condenser comprises a heat supply network water supplementing system and a heat supply network gatewaystation. The heat supply network water supplementing system comprises the steam condenser and a condensation water pump, a hot well of the steam condenser is connected with a heat supply network watersupplementing pipe, and the steam condenser is connected with the condensation water pump through a pipeline; and an outlet of the condensation water pump is connected with a heat supply network water return pipeline, and the heat supply network water return pipeline is connected with the heat supply network gateway station. The heat supply network gateway station system is provided with no heatsupply network dust collector or a water supplementing pump, supplementing water of the heat supply network water supplementing pipe directly supplements the hot well of the steam condenser, enters the heat supply network water return pipeline after being boosted by the condensation water pump, and enters the heat supply network gateway station through the heat supply network water return pipeline. According to the arrangement, equipment investment can be reduced, the high-pressure steam consumption of a heat supply network deaerator is avoided, and the steam extraction flow of a turbine is reduced.