A starting circuit for a single-phase AC motor, comprising a main winding, a detecting circuit, a rectifying and filtering circuit, a triggering circuit, a switching circuit and a starting winding. The detecting circuit is connected in series to the main winding for transforming current parameters thereof into detecting signals. The switching circuit is connected in series to the starting winding. The rectifying and filtering circuit processes the detecting signals and the processed detecting signals to the triggering circuit. The triggering circuit enables or disables the switching circuit according to the detecting signals, so as to energize or deenergize the starting winding. The starting circuit features high reliability, long lifetime, simple circuit structure, low cost, and small size.