The present disclosure relates to a data analysis method and a data analysis system thereof. The data analysis method includes steps of: receiving a first learning content data, and adding multiple first segmentation marks to the first learning content data to divide multiple first learning sections on the first learning content data. The first learning sections are arranged according to a time axis. Searching a first keyword string corresponding to each first learning section from the first learning sections. Receiving a analysis command, and analyzing the analysis command with the first keyword string of each of the first learning content data to obtain multiple first similarities, corresponding to the analysis command and each of the first learning sections. Finally, searching for the first learning section with the highest similarity.