The invention discloses a warehouse monitoring system based on signal conditioning. The system comprises a wireless sensor network for monitoring the warehouse environment, a cloud data server, a face recognition module, an illegal opening monitoring module, a wireless transmission module, an automatic opening module, an infrared detection module, an automatic shutdown module, an SMS alarm module, a field acousto-optic alarm module and a real-time monitoring platform. The wireless sensor network comprises gateway nodes, and a plurality of sensor nodes arranged throughout the warehouse. The sensor node comprises a temperature detection module, a light intensity detection module, a smoke sensor and a signal conditioning circuit. The signal conditioning circuit comprises a DC power supply, a first resistor to a tenth resistor, a first capacitor to a fifth capacitor, a first operational amplifier, a second operational amplifier, a triode, a network signal input terminal, and a network signal output terminal. The warehouse monitoring system is based on signal conditioning and can accurately detect the environment in the warehouse, and also can issue an alarm in time.