The invention discloses a variable voltage variable current alternating intermittent pulse charger, which consists of a shell, an operation panel part and a working part. The operation panel part consists of a panel, a DC ammeter, a DC voltmeter, a power indicator lamp, a starting indicator lamp, a positive charging indicator lamp, a reverse charging indicator lamp, a power switch, a regulation potentiometer and a starting button. The working part consists of a two-way silicon controlled rectifier, a control transformer, a power alarming board, a loudspeaker, a rectification unit, a current divider, two control relays, a DC voltage identification board, a fuse and a cooling fan. The charger performs charging in form of variable current variable voltage positive and reverse pulse triggering, and has a rationally designed rated charging current value; after a pulse voltage output by the control transformer is rectified, a DC pulse voltage is output; and in each charging cycle, an alternating intermittent space effectively releases inter-plate charges, delays polarization and reduces pressure and temperature provided in a lead-acid storage battery in charging.