The invention discloses a pipe network pressure-superposed tank type flow stabilization compensation secondary water supply device. The pipe network pressure-superposed tank type flow stabilization compensation secondary water supply device is mainly composed of a flow stabilization compensation tank, a negative pressure eliminator, a water shortage signal transmitter, a flow adjusting valve, a water quality sterilizer, a water pump, a flow detecting device and a control cabinet; the flow stabilization compensation tank is of horizontal type stainless steel structure; an inner sealing head is arranged inside the flow stabilization compensation tank to separate the flow stabilization compensation tank into a water storage cavity and a flow stabilization cavity; the negative pressure eliminator and a pressure meter are installed at the top of the water storage cavity; and the water shortage signal transmitter is installed at the bottom of the water storage cavity, and a water storage opening is formed in the water storage cavity. The pipe network pressure-superposed tank type flow stabilization compensation secondary water supply device has the beneficial effects that the flow stabilization compensation tank is of a dual-cavity structure composed of the flow stabilization cavity and the water storage cavity, and the adjusting volume of compensation of the tap water inlet amount can be increased through the water storage cavity; meanwhile, the flow control valve is arranged so as to be used for controlling pressure drop losing of tap water inlet; the pipe network pressure-superposed, non-negative pressure, flow stabilization and water storage compensation adjusting secondary water supply effect is achieved; and the pipe network pressure-superposed tank type flow stabilization compensation secondary water supply device has the beneficial effects of being compact in structure, less in occupied land, sanitary, good in water supply safety, saving energy and the like.