The research study was conducted in Hama Governorate during the agricultural season of 2010 - 2011 through a stratified random sample of 201 farmers who cultivate irrigated durum wheat in the research area in order to measure the yield gap, the productive efficiency divergence among farmers and to determine the effect of using different amounts of the productive factors in the production process. It also aimed to determine the contribution level of these factors in the gap formation, as well as to determine the production phase in which farmers of the sample stand. Descriptive analysis methodology in addition to the multiple regression technique were used to estimate production functions. Results showed a yield gap up to 32.6% between farmers in the first phase and those who are in the fourth phase. The reason why productivity in large size farms was higher than in small size farms that the second production stage, the profitable one occurred in large size farms, while the first production phase occurred in small economic capacity farms. So, another combination of the production inputs can be used in order to reach a marginal product value which equals the price value and to increase the production level plus the productivity of the farmers in the research area.