The frequency of drought and heat stress events has increased due to global climate change, posing a significant threat to current and future cotton production. Understanding the fundamental mechanisms of adaptation to heat and drought stress is essential for improving cotton resilience. Three TNAU pre-release cotton cultures (TVH002, TVH003 and TVH007) and a check variety (KC3) were subjected to drought and heat stress at two growth stages: squaring and flowering. Plants were exposed to 45 % Pot Capacity (PC) under drought stress conditions and Ambient temperature + 5 °C under heat stress condition respectively. TVH002 exhibited the highest drought tolerance, while the flowering stage was more susceptible to drought than the squaring stage. Genetic analysis revealed that Excised Leaf Water Loss (ELWL) and Relative Water Content (RWC) exhibited high heritability, along with large genotypic and phenotypic coefficients of variation. These traits can serve as reliable indicators for drought screening in cotton breeding programs. Proline accumulation showed the highest heritability (0.81), followed by antioxidant enzyme activity (0.77) and ELWL (0.72), indicating strong genetic control. Traits with high heritability and low GCV-PCV differences, such as proline accumulation and relative water content, are ideal for selection in breeding programs for drought and heat stress tolerance.