Abstract: Cultivated plants are often exposed to different types of environmental stress which has a negative effect on the vegetative and reproductive development. In the current study the influence of water deficit on phenological and morphological characters of different tomato genotypes was investigated. The experiment was conducted at the Maritsa Vegetable Crops Research Institute in two consecutive years (2016-2017) with 11indeterminate and 13 determinate tomato accessions grown under optimum and 50% reduced irrigation. The results showed that the plants of indeterminate and determinate tomato types answered the water deficit with a decrease of the fruit number (53.0% and 32.2% respectively), fruit weight (42.9% and 19.2%), plant fresh weight (36.0% and 37.5%), flower number (19.1% and 11.5%), pericarp thickness (19.1% and 10.6%), fruit length (17.9% and 13.5%) and fruit width (15.9% and 8.1%). In the predominant part of the accessions grown in the reduced watering regime the total soluble solids were higher than these of the accessions grown in the optimal one. Strong to very strong positive correlations of plant height, flower number, fruit number and fruit weight in optimal irrigation with the same characters in reduced irrigation were found.