Provided are a device and system for generating a low frequency alternating electric field, and a signal regulating method. The device for generating a low frequency alternating electric field includes: a direct current power supply module, an input control module, a transformer, an output control module, and a discharge module. An output end of the direct current power supply module is coupled with an input end of the input control module. An output end of the input control module is coupled with a primary side winding of the transformer, one end of a secondary side winding of the transformer is coupled with an input end of the output control module, an output end of the output control module is coupled with the discharge module, and the other end of the secondary side winding of the transformer is coupled with a ground equipotential point.