A data processing method and device for a Light emitting diode (LED) Television (TV), and an LED TV are disclosed, the data processing device includes: a signal processing chip configured to perform mode conversion on a received TV signal so as to obtain a first video signal of a preset mode; and a video processing chip connected to the signal processing chip and configured to perform clock synchronization processing on the first video signal so as to obtain a second video signal and output the second video signal to an LED display. The problem in the prior art that an LED TV can only display a TV signal of a single mode is solved, thereby achieving the effect that the LED TV can display videos of various modes and various formats.