The invention provides a testing device and method for a power frequency follow current interruption capability of a 35kV lightning protector. The testing device comprises a charging unit CHA, a powerfrequency power supply P, an impact current unit ICG, a control unit C, a protection reactor L2, a current detection unit and a voltage detection unit. According to the device provided by the invention, standard 4/10 impact current is output through the ICG and 35kV rated network voltage is generated through an LC topological circuit; the standard 4/10 impact current and the 35kV rated network voltage are applied to two ends of the 35kV lightning protector in a time sharing manner through phase control of the control unit, and the power frequency follow current interruption capability of the35kV lightning protector is verified. According to the device provided by the invention, a high-voltage impact current source is electrically connected with the power frequency power supply through aninsulating matching design; the device has the advantages of small occupied area, low testing cost, capability of ensuring the testing success rate by a one-button start function and the like.