An amplification control method and circuit, a sensitive amplifier and a semiconductor memory are provided. The method includes that: a preset instruction is received, and an isolation power value and a control instruction signal are determined according to the preset instruction; an isolation control signal is generated according to the isolation power value and the control instruction signal; and an amplification circuit receives the isolation control signal and a target signal to be processed according to the preset instruction, and processes the signal to be processed and completes the preset instruction.