A mobile communication terminal and its operation method that can compensate the data synchronized error when play the multimedia data. The terminal includes: the speaker that is used to output the playing multimedia data; the display unit that outputs the text data; the multimedia controller that analyze and play the multimedia data, compensate the error of the outputting time by the multimedia play, and output the compensative text data; the controller that manage data and control the drive of the speaker and display unit. The method is: computes the tense error between the output time information and the audio signal of the actual output, and also computes the appearing proportion tense error that is proportional with the outputting time, compensates the tense information based on the computing tense error and proportion tense error.