The invention relates to a distribution network reactive power compensation control method and a device capable of suppressing resonance. According to the control method, a control device is adopted to acquire three-phase voltage values and current values of a distribution network system to calculate three-phase current fundamental component effective values, three-phase voltage and current distortion rate variations, conjunction active and reactive power effective values and a power factor COSphi, on the basis of a conventional reactive power compensation control strategy, a judging function of using the current fundamental component effective values and the harmonic voltage and current distortion rate variation range to recognize whether resonance happens to the system is added, and in the case of resonance, a group of capacitors is cut off quickly to remove the resonance condition to suppress the resonance. The control device is composed of an electrical parameter and switching value detection and conditioning unit, a core control unit, a communication unit, a man-machine interaction unit and an output execution unit. Hardware is replaced by software, and the defect that the resonance can not be suppressed in the conventional reactive power compensation control method can be effectively overcome.