A diaphragm pump and an electric sprayer, and the diaphragm pump comprises a U-shaped yoke (100), four permanent magnets and an oscillating arm (400), wherein end faces (111, 121) of two legs (110, 120) of the U-shaped yoke can generate alternating magnetic polarities under the control of a control circuit (300). The four permanent magnets are fixedly mounted on an inner arm (420) of the oscillating arm by means of a second yoke (500). The four permanent magnets are a first permanent magnet (610), a second permanent magnet (620), a third permanent magnet (630) and a fourth permanent magnet (640), respectively, which are sequentially distributed in a same circumference centered at a pivot point. The first permanent magnet and the fourth permanent magnet are of the same polarity at radial end faces (611, 641); the second permanent magnet and the third permanent magnet are of the same polarity at radial end faces (621, 631), which is opposite to the polarity at the radial end face of the first permanent magnet. When the coil (200) is energized, the four permanent magnets generate torque in the same direction of rotation, and under the action of the alternating magnetic polarities at the end faces of the two legs of the U-shaped yoke, the four permanent magnets perform reciprocating oscillation; as a result, an outer arm (430) of the oscillating arm (400) brings a diaphragm push-and-pull rod (920) to squeeze the diaphragm, thus changing the size of a fluid chamber (910), thereby achieving intake and discharge of liquid.