Context: Games involve people to a large extent where they relate themselves with the game characters; this is commonly known as game immersion. Generally, some players play games for enjoyment, some for stress relaxation and so on.Game immersion is usually used to describe the degree of involvement with a game. When people play games, they don’t necessarily realize that they have been dissociated with the surrounding world. Real world dissociation (RWD) can be defined as the situation where a player is less aware of the surroundings outside the game than about what is happening in the game itself. The RWD factor has been expected to measure the losing track of time, lack of awareness of surroundings and mental transportation. Objectives: In this thesis, we measure and compare the difference in game immersion between experienced and inexperienced players using RWD factor. In addition, the study involves exploring the significance of game immersion and various approaches used to measure it. Methods: In this study literature review has been carried out to explore the meaning of game immersion and further user studies in the form of an experiment has been conducted to measure game immersion between experienced and inexperienced gamers. The game immersion has been measured using the real world dissociation (RWD) factor. After the experiment has been conducted, a statistical technique has been carried out to measure the difference in game immersion among the two groups. Results:The empirical investigation on the measurement of game immersion has been done using RWD factor. The results state that the significance value is less than 0.05 and hence null hypothesis is rejected for both the games. The measurable difference has been calculated by using Cohen’s d effect size between experienced and inexperienced players. The Cohen’s d value between experienced players and inexperienced players for Dota 2 is 0.7423 and CS:GO is 0.8383. Conclusions: After analyzing the data and calculating the effect size, the overall results state that inexperienced group of players are more immersed than the experienced group of players when measured by RWD factor. Hence it can be concluded that irrespective of the game played, inexperienced players are more dissociated from the real world than the experienced players.