The invention relates to a self-adaptation control method of a pulse-modulated signal in electric vehicle charging. The method comprises the following steps of: (1) reading a maximum supply current set by a current power supply unit, and judging; (2) detecting a signal at a charging part connected with a vehicle until the signal is 6V; (3) calculating a duty ratio of a corresponding national standard pulse modulation signal for testing the maximum supply current Itest* 90%; (4) continuously detecting a charge current until a time counter is increased to be setting time; (5) if the charge current is consistent with national standards, carrying out a step (6), and if the charge current is consistent with IEC61851-1 standards, carrying out a step (7); (6) adjusting a PWM (Pulse-Width Modulation) signal according to the national standards, and carrying out a step (8); (7) adjusting the PWM signal according to the IEC61851-1 standards, and carrying out a step (8); (8) continuously judging standards met by the current; and (9) setting the duty ratio of the PWM signal corresponding to an Imax current, and outputting. According to the self-adaptation control method of the pulse-modulated signal in electric vehicle charging, an electric vehicle can be charged quickly and safely, and the ability of products adapting to different charge standards is improved.