In the study, inverted Adamset F1 hybrid tomato cultivar was used. The plants were grown in hydroponic culture using Hoagland nutrient solution at a light intensity of 400 µmol m-2 s-1, at 25 oC, 65% humidity, in a controlled climate room with a 16/8 hour light/dark photoperiod. 0.016 ppm, 0.021 ppm, 0.026 ppm, 0.031 ppm, 0.036 ppm, 0.041 ppm and 0.046 ppm doses of Manganese (Mn) were applied to the nutrient solution. When the plants had 4-5 true leaves, polyethylene glycol (PEG-6000/5%) was added to the medium and drought was applied. On the 7th and 14th days of drought application, samples were taken from the plants. In order to determine the effects of Mn element applications on some growth parameters of plants in the case of drought stress, some growth parameters of plants were examined. When different doses of manganese were applied to tomato plants under drought stress, it was determined that the optimum manganese doses that had a positive effect on plant growth of tomato plants were 0.031 ppm and 0.036 ppm.