In arid and semiarid areas like the Cholistan Desert in Pakistan, water shortage continues to be a significant limitation to tomato production. This experiment was carried out to assess the drought resistance of 20 tomato (Solanum lycopersicum L.) genotypes to different degrees of water stress to determine which genotypes had better morphological and physiological resistance. The experiment was designed as a randomized complete block design (RCBD) with five replications, and four irrigation regimes, including 100% field capacity (Control), 75%, 50%, and 25% water availability. The experimental evidence indicates that the shoot length (SL) was reduced by up to 55% and the root length (RL) was reduced by an average of 48% in all the drought treatments imposed. It was interesting to note that genotypes G4, G17, and G18 performed better, maintaining SLs that were 25%-35% longer and shoot/root biomass ratios that were 20-40 times higher than the most drought sensitive genotypes (G10, G11, G19, and G20) in severe drought conditions (25% of the allotment of irrigation). In particular, genotype G18 retained 70% of its shoot dry weight (SDW) and 65% of its root fresh weight even in the most extreme stress situation (T4). Also, genotypes G6, G13, and G14 showed improvements in water use efficiency and transpiration control. Principal component (PC) analysis indicated that the first two PCs explained over 57% of the phenotypic variation, highlighting the importance of SDW, RL, and photosynthetic performance as important factors of drought tolerance. In conclusion, genotypes G4, G17, and G18 should be developed further and used in agronomics in arid environments, which is explained by their outstanding performance indicators. The integration of physiological and morphological traits provides a robust framework for selecting drought-resilient tomato cultivars.