In order to evaluate the effects of drought stress and defoliation on sunflower a study was conducted under controlled conditions. Treatments were combination of three levels of drought ((100, 60 and 30 percent of Field Capacity (FC)) and three levels of defoliation (control, removal of 4 and 6 leaves from lower part of plant) which were laid out on a Completely Randomized Design with four replications. Drought stress was applied from 4-leaf- stage to the end of plant growing period and leaf removal was conducted in the heading stage. Results indicated that drought stress affected most of the measured parameters. Plant height, plant dry matter , stem diameter, head size, seed number/head, 100-seed weight and seed weight per head was declined on drought stress treatment as compared to control. SPAD reading increased as drought stress increased. Defoliation caused an increase in SPAD and a decrease in seed number/head. Leaf number was not affected by either drought or defoliation.

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