A charging load detection circuit includes a charging circuit, a frequency generation unit, and a control unit. The control unit controls the frequency generation unit to generate a pulse voltage with a fixed first frequency and a fixed first amplitude, and the frequency generation unit provides the pulse voltage to an output terminal of the charging circuit. The control unit detects whether a load is coupled to the output terminal by detecting whether the first frequency and the first amplitude are varied, and controls connecting or disconnecting a charging path of the charging circuit according to whether the load is coupled to the output terminal.