The purpose of this thesis is to study the usage of Mobile Game and its user behavior in Taiwan. We conduct an empirical market investigation associated with statistical analyses, and conclude the following findings. The users of the Mobile Game are significantly concentrated in the young-age consumer groups, including students at schools and new entrants of social freshmen. These groups often play the Mobile Game not during the daily class period for the students and not during the office hours for the social freshmen. According to the empirical evidences, we suggest that the advertisement companies can utilize the after-class and off-duty time periods to launch it performance in order to earn more profit.