The invention provides a testing device for a rotating table frequency response. The device comprises a signal generating and colleting component and a computer where a signal analysis MATLAB program operates. In the using process, the excitation signal output end and the steady state signal input end of the signal generating and collecting component are connected with a tested system, and a first CAN communication interface is connected with the computer through a USB-to-CAN module. According to characteristics and testing requirements of the tested object, an amplitude value and frequency for testing an excitation signal are set on the CAN communication interface to test the interval between frequency points and test the output mode of the signal. Under the condition that no sensor is additionally arranged, a sensor arranged on the tested system is used for collecting an analogue or digital steady state response signal of the tested system, the effectiveness of the tested signal is automatically judged, and prompt information is output.