The invention discloses a method for measuring the rod drop time of a linear motor control rod drive mechanism. Measurement is carried out by using back electromagnetic force voltage generated by a magnetic line cut by the linear motor control rod drive mechanism after being powered off, and the control rod drive mechanism is connected with a control power supply. The method comprises the steps of (1) pre-arranging a test point on a connection line of the control rod drive mechanism and the control power supply; (2) connecting a waveform display device and the test point, and collecting a back electromagnetic force voltage signal generated by the magnetic line cut by the linear motor control rod drive mechanism after being powered off; (3) displaying a corresponding waveform image by the waveform display device on the basis of the collected back electromagnetic force voltage signal; and (4) calculating the rod drop time of the control rod drive mechanism on the basis of the waveform image displayed by the waveform display device, thereby achieving the technical effects that measurement operation is simple, data is stable and easy to read and the measurement result is accurate.