This experiment studies effect of plant growth regulators [Krezacin (5, 10 and 15 ml L-1) and Energen (10, 20 and 30 ml L-1)] on morphological and biochemical characteristics of tomato plants (Mariana cultivar). Applying Krezacin 15ml L-1 increased Plant height, number of leaves/plant, number of branches/plant and leaf area index (LAI). The same result obtained after applying Energen 30ml L-1 except the maximum number of leaves/plant which obtained from Energen 20ml L-1. The longest period to flowering obtained from plants which treated with Energen 10ml L-1. Using Energen 30ml L-1 recorded the maximum values for the weight of fruit (g), Sugar contents% and PH. Whereas Krezacin 10 ml L-1 recorded the highest values for number of fruits/plant, titratable acidity % and Ascorbic acid con-tents (mg). the aximum amount from carotenoids obtained from plants which were applied by Energen 20 ml L-1, While statistically, No significant differences were observed in content of nitrate for all treatments.