Many studies to date have tried to determine whether or not “playing violent video games would increase aggressive behavior” . Previous studies can be separated into experimental studies, survey studies, and they often indicate the possibility that video games could have adverse effects on aggressive behavior. In lab experiments, those who are in the experimental class play aggressive video games in a laboratory, and their behavior is later compared with that of the control group. In general, laboratory experiments have a strong ability to identify cursory relationships; however, they have problems that experimental scenes are artificial and that recognizing causal relationships are usually short-term relationships. Meanwhile, in survey studies, the amount of video game usage and aggression of the children are measured to examine the correlation between them. Although some previous debates indicate that there are a significant positive correlation between the amount of video game usage and aggression that the children have, debates cannot identify the cause and effect even though they can identify correlations. Therefore, survey studies, overcome the artificial problem, but are still unable to identify causal relationships. Although it is still a survey study, a panel study can to some point get closer to pinpointing causal relationships than other methods that acquire correlations in one-time studies. A panel study is a survey study in which the same variables are measured multiple times with the same subjects. Causal relationships can be estimated by analyzing data obtained through this method. There have not been many panel studies so far; therefore, we conducted a panel study in order to examine the effect of video games on aggressive behavior in real life. So far, the amount of time spent on using video games and games of specific genres of murder and violence, were used as independent variables in panel studies. In addition to these variables, we measured the amount of time that the participants were exposed to violent scenes as well as their fondness for violent games. Although the amount of video game usage changes with the conditions that the contributors are in, preference usually stays the same; therefore preference has the advantage that it remains stable in terms of time. We also studied not only aggressive behavior, but also per usual behavior as dependent variables. A negative relationship between violent video games and prosocial behavior has been recorded. We used the amount of usage and preference for violent games as video game variables, and carefully examined the connections between the video game variables and dependent variables. As a result, we suggested that there was a significantly clear negative correlation between the amount of video game usage and per usual behavior, and that children exhibiting strong preference for violent games were likely to show aggressive behavior and unlikely to show prosocial behavior compared to those displaying weak preference for violent games. In this study, we conducted a panel study to examine that playing violent video games will cause an major increase in aggressive behavior and a decrease in per usual behavior. This is why our society today shows so much hatred and aggressive, unnecessary behavior.