The invention discloses a method for displaying a 3D image, a television and glasses. The method comprises: receiving a 3D image signal which comprises a frame of left eye signal and a frame of right eye signal that are continuous; multiplying the frequency of the 3D image signal to obtain n continuous frames of left eye signals and n continuous right eye signals, wherein n is the number by whichthe frequency is multiplied and is more than or equal to 2; and displaying the n continuous frames of left eye signals and the n continuous right eye signals by using an LED driving signals for drive, wherein the LED driving signal corresponding to the first frame of left eye signal in the n continuous frames of left eye signals is closed, the LED driving signal corresponding to the nth frame of left eye signal is open, the LED driving signal corresponding to the first frame of right eye signal in the continuous n frames of right eye signals is closed and the LED driving signal corresponding to the nth frame of right eye signal is open. In the invention, mutual interference of left and right frames is avoided, the energy consumption of a backlight source is reduced and the cost of the whole machine is reduced.