The invention discloses an intelligent sine-wave voltage conversion circuit based on a PFC (power factor correction) forward half-bridge. The circuit comprises an input rectifier filter unit, a PFC voltage boosting unit, an isolated two-transistor forward converter and an inversion reverse-phase unit, wherein the isolated two-transistor forward converter comprises a first switch tube, a second switch tube, a first diode, a second diode, a third diode, a fourth diode, a transformer and a filter inductor; the inversion reverse-phase unit comprises a fourth switch tube, a fifth switch tube, a third electrolytic capacitor, a fourth electrolytic capacitor and a first filter inductor, a grid of the fourth switch tube and a grid of the fifth switch tube are used for accessing two ways of PWM (pulse width modulation) pulse signals with opposite phases respectively, a source of the fourth switch tube is further connected to the front end of the first filter inductor, a negative pole of the third electrolytic capacitor is connected to a positive pole of the fourth electrolytic capacitor, and the rear end of the first filter inductor and the negative pole of the third electrolytic capacitor are taken as output ends of the inversion reverse-phase unit. With the adoption of the circuit, PF (power factor) value and output voltage quality can be improved.