Five improved genotypes of durum wheat (T. turgidum var. durum) (Lahn, Cham1, Gezira17, Bouhouth 5, and Acsad 65) were planted under the conditions of the agricultural region (Bouka) of the Faculty of Agriculture- Tishreen University during the agricultural year 2002-2003, with a split-plot arrangement to study the effects of flag leaf removal on grain yield and its components.The genotypes differed significantly in flag leaf area, stomatal frequency, yield parameters and protein content. Flag leaf removal significantly reduced plant height, number of spikelets/ spike, number of grains/ spike, 1000 kernels weight and grain yield, while grain protein content significantly increased. There was a positive correlation between the flag leaf area and 1000- kernels weight and grain yield, but protein content was negatively correlated with grain yield.