The invention relates to the technical field of power grid equipment detection and particularly relates to a capacitive voltage transformer amplitude-frequency characteristic detection system and method. The system comprises a controllable frequency generation unit, a detection loop and a calculation processing unit. The controllable frequency generation unit is connected with the detection loop,a high-voltage side of the detection loop is connected with two buses in parallel, the two buses are respectively connected with a primary side of a first detected capacitive voltage transformer and aprimary side of the second detected capacitive voltage transformer, and a voltage detection unit is respectively connected with a secondary side of the first detected capacitive voltage transformer and a secondary side of the second detected capacitive voltage transformer. The invention provides a unified standard capacitive voltage transformer amplitude-frequency characteristic detection method,the amplitude-frequency characteristic of the capacitive voltage transformer can be automatically and accurately detected, the amplitude-frequency characteristics of the secondary side voltage of thecapacitor voltage transformer is drawn, therefore, the stable operation of the capacitive voltage transformer is ensured, and the development of the electric energy quality of a power grid is furtherpromoted.