Aims: This research was carried out to evaluate the yield (seed yield), yield parameters (weight of 1000 seeds, dry matter accumulation), vegetative (plant weight, leaf area index) and physiological characteristics (stomatal conductance, chlorophyll content) of soybean as a response to different irrigation levels in East Mediterranean climatic conditions (Hatay Region). Methods and Results: In the experiment, five irrigation level (as a depletion of available water content water, 25(I25), 50(I50), 75(I75), 100(I100) and 125%(I125) were treated. Drip irrigation systems was employed and, irrigation frequency was planned as once a week troughout the irrigation season. According to results, the amount of applied irrigation water, evapotranspiration and water use efficiency ranged from 201.5-807.1 mm, 251.5-781.7 mm, 0.59-0.93 kg da mm-1 , respectively. The seed yields in inoculated and uninoculated treatments were 218.90, 328.07, 431.80, 449.33, 468.27 and 198.56, 295.80, 409.10, 473.03, 518.73 kg da-1 in I25, I50, I75, I100, I125 irrigation levels, respectively. The yield response to water (ky) was calculated as 0.63-0.90. Conclusions: The amount of irrigation water were found to be influential on the seed yield, the weight of 1000 seeds, the fat and protein contents, and dry matter content of the plant in the blooming and harvest. But no effect on the number of pod and flowers in blooming were observed. The chlorophyll content and stomatal conductance tended to decrease in all treatments toward the end of the irrigation season. Significance and Impact of the Study: In the Amik Plain, no detailed study on soybean water yield relationships conducted. This research revealed the need for irrigation water and plant water consumption of soybean in Amik Plain.