A control circuit of a small night lamp comprises a power circuit having a battery, a solar cell, the battery being installed with a switch for controlling the turning on and off of the power; a sound sensing circuit having a sound pickup, two transistors; the sound pickup serving to sense sounds and then to conduct the transistors; a light circuit having a plurality of LED lights; and a main control circuit having a microprocessor which is connected to the sound sensing circuit and the LED lights; the main control circuit being actuated by the transistors of the sound sensing circuit; when the main control circuit is actuated, all the LED lights lighting up or the LED lights lighting up in turn.