The invention provides a liquid crystal display television and a data processing device thereof. The data processing device comprises a system board and a timer controller. The timer controller comprises a receiving module and a microcontrolling module. The system board is used for sending a VBYONE signal to the receiving module. The microcontrolling module is used for converting each frame signal of the VBYONE signal into digital data, generating a new frame signal according to the two adjacent frame signals and inserting the new frame signal between the two adjacent frame signals after it is judged that a difference value between the digital data of two adjacent frame signals is greater than a reference value, and keeping a time interval between the two adjacent frame signals unchanged.