In this study, the effects of deficit irrigation along with a foliar application of silicon on growth, yield, and quality of tomato (Lycopersicon esculentum L. cv BHN) were evaluated. This experiment was conducted as a factorial arrangement in a completely randomized design with three replications. Tomato plants were planted in pots containing coco-peat and perlite (80:20 v/v). The plants were treated with different irrigation levels (60, 80, and 100% full irrigation) and different levels of silicon (0, 100, and 200 mg L^-1). Results showed that with an increase in irrigation levels vegetative growth and fruit quality was improved. The highest plant height and fruit number were found in 100% water requirement. Application of 200 mg L^-1 silicon significantly increased fruit number and yield in 60% deficit irrigation. Deficit irrigation significantly increased catalase and peroxidase enzyme activity. The application of 100 mg L^-1 silicon could increase TSS in 80% deficit irrigation. Overall, it seems that foliar application of silicon (200 mg L^-1) could alleviate the negative effects of drought stress in tomato and improved growth, yield, and fruit quality under drought stress conditions.