The invention discloses a high-frequency high-voltage generator for 16KW pet X-ray machines. The high-frequency high-voltage generator is mainly composed of a frame (1), a master circuit board (2), a high-tension oil tank (3), a 12V switch power supply (4), 48V switch power supply (5), a power management circuit board (6), a filter rectifier unit (7), a fuse (8), an energy-storage capacitor (9), a main inverter unit (10), a magnet ring (11), a blocking condenser (12), an energy storage capacitor tray (13), a discharge resistor (14), a charging resistor (15), an anode starting capacitor (16), an anode connector bar unit (17), a power connector bar unit (18) and a rotating anode transformer (19). The high-frequency high-voltage generator is simple in structure, reasonable in component arrangement and simple in wiring, almost no impact is caused to on network voltage under full power exposure, high-power output can be stabilized, requirements of customers on power can be met, and requirements on power grid can be reduced.