The invention discloses an undervoltage latch circuit with a band gap reference structure, comprising a voltage divider, a band gap reference circuit, a comparer and a logic circuit. The undervoltage latch circuit is characterized in that the band gap reference circuit and the comparer are realized by adopting a band gap reference comparer consisting of the band gap reference structure and a load, a branch voltage output end of the voltage divider is connected with a comparison voltage input end of the band gap reference comparer, and the output end of the band gap reference comparer is connected with the input end of the logic circuit and form a control output end of the undervoltage latch circuit after being deformed by the logic circuit; and a feedback control loop is arranged between the logic circuit and the voltage divider, and the logic circuit makes the voltage divider output relatively be higher branch voltage by the feedback control loop when the band gap reference comparer outputs a high level. The invention establishes the band gap reference comparer by designing the band gap reference structure and has the advantages of remarkably simplified circuit structure, smaller area of the circuits, lower cost, faster response speed, smaller temperature drift and low power consumption.