The invention relates to a sensitive amplifier circuit of a semiconductor memory, a working method and the application thereof. The amplifier circuit comprises a Schmidt buffer, an inverter (1), an inverter (2), a storage cell, and a current detector which is used for detecting the ampere of a current flows through the storage unit, converting the ampere into a voltage signal and outputting the voltage signal. The storage unit, the current detector, the Schmidt buffer, the inverter (1) and the inverter (2) are connected in sequence. The current detector detects the ampere of the current flowing through the storage unit, converts the ampere into a voltage signal and outputs the voltage signal. The Schmidt buffer reshapes the output voltage signal. The inverter (1) inverts the output signal of the Schmidt buffer. The inverter (2) inverts the inverter (1) and provides the carrying load ability for the output of the sensitive amplifier circuit. The sensitive amplifier circuit is applied to a storage circuit. The invention has the advantages of simple structure, lower power, lower requirement for working voltages, high stability and application in various storage circuits.