Abstarct: Green sweet pepper is a popular spices with a sweet taste that can be used in almost all foods. Water deficient is one of the most important factors limiting greenhouse pepper production. So, in order to study effects of amino acids on drought stress in green sweer pepper productions, an experiment was conducted baxsed on split plot design. The main factor was irrigation schedule at two levels of 50% of field capacity and 100% of field capacity (control) and subplot was amino acid application with three levels of control (0), 150 and 300 mg/L in four replications. Vegetative and reproductive traits and yield in green sweet pepper (Lambard) were assessed. The results showed that drought stress significantly reduced vegetative growth, quantity, quality and yield of sweet pepper fruits. Foliar application of amino acid significantly increases leaf area, but by decreasing irrigation levels, leaf area decreases. The number of fruits and yield increased significantly in 300mg/l concentration of amino acid fertilizer. The highest yield, 0.97 kg/plant, was observed in 300 mg/L amino acid containing fertilizer in full irrigation and treatment of drought stress, 50% of field capacity, without amono acid foliar application with an average of 0.70 kg/plant had the lowest yield. By increasing the level of amino acid fertilizer, the amount of chlorophyll increased about 20% and reached to 47%, and the amount of vitamin C under stress conditions was 29 mg/100 g, which reached to 52 mg/100g with application of 300 mg/L fertilizer containing amino acid. Application of fertilizer containing amino acids significantly increased the yield efficiency and quality of pepper and reduced the destructive effects of stress.