DescriptionDue to the controversial debates, skepticism and speculations around Genetic Modified (GM) crops, substantial research has been done on the allocation of welfare implications of GM crops. However, different procedures, various data sources and economic models are used to study commercialized GM crops around the world. Therefore mixed conclusions were conducted. Some papers mentioned benefits from farm producer side; some focused on research of willingness to pay among consumers; while others were asmore interested in market prospect. As a result, is has become difficult to effectively summarize the benefit of adopting GM crops and explain the large study-to-study variations of surplus estimation. This thesis presents a meta-analysis of 58 primary studies with a total of 119 GM crops evaluations, aiming to summarize previous studies on economic surplus of GM crops which are not conditional from a single research study and to identify the determinants of the farmer surplus, GM seed company surplus and consumer surplus of GM crops, from analysis and comparison those broad range data set. This thesis finds that GM seed companies and farmers gained different surplus based on geographic locations. On the other hand, research methods might affect farmer surplus estimation but not GM seed company surplus.