The invention provides a switch-off phase control based intelligent alternating current contactor. The intelligent alternating current contactor comprises an electromagnetic type alternating current contactor and an intelligent controller consisting of a signal collection module, a main control module, a power supply module, a coil current control module and the like; the signal collection module collects current of any one phase of the alternating current contactor and sends the current to the main control module; the power supply module converts the alternating current generated by the coil on the alternating current contactor into direct current and sends the direct current to the main control module; when the main control module detects that the direct current voltage value is less than a preset numerical value, a switch-off instruction is output after the current collected by the signal collection module achieves a phase angle with the minimum switch-off energy sum, and the coil current control module controls the switch off of the coil current; or when the main control module detects that the direct current voltage value is greater than or equal to the preset numerical value, a switch-on instruction is output, and the coil current control module controls the switch-on of the coil current. By the implementation of the switch-off phase control based intelligent alternating current contactor, the switch-off electric arc energy can be reduced by changing the switch-off policy, so that lower switch-off electric arc energy can be obtained, and the service life of the intelligent alternating current contactor can be prolonged.