This study was conducted to assess and find out the impact of on-line gaming on the academic performance and social behavior of the students in the Polytechnic University of the Philippines-Laboratory High School. Furthermore, this study sought answers on the significant relationship between playing on-line games and academic performance and to social behavior of the students. The study revealed that boys are more of a player compared to girls who often play games that require three or more players like League of Legends, Clash of Clans, Crossfire and many more to mention. It is also stated that those who play online games are around 14-15 years old who are believed to be in the Grade 8 level. These students who often play games have an average weekly allowance of 101 pesos to 500 pesos. Playing online games do not affect their grades badly for they know how to limit themselves. They know that they need to control themselves in order to function well in their class that is why they only play games during vacation and weekends with a lot of time compared when they have classes. Even though they play online games; they know how to socialize well and they can perform very well when it comes to academic performance. However, it is inevitable not to play even for half an hour especially when they are accustomed to it. Therefore, it is just a matter of discipline. Keywords: On-line Gaming, Social Behavior, Curriculum, Academic Performance.