This study investigates the relationship between thermos-physical parameters specifically temperature and humidity and the hatching success of chicken eggs from indigenous Indian breeds such as Kaveri and Kadaknath. While existing research has largely focused on ducks and turkeys or has addressed parameters individually, few studies have examined their combined effects on native chicken breeds. This research is aimed to fill that gap by analysing optimal incubation conditions and identifying critical thresholds. Experimental results suggests that a moisture level of 55% to 60% and relative humidity 65% to 70& during final 2 to 3 days of incubation significantly improves the rate of hatching. The optimal temperature range was found to be between 26 degrees to 32 degrees. Deviations beyond these thresholds were associated with increased fungal growth, shell break and higher rate of egg wastage. These findings provide valuable insights for developing efficient and breed specific incubation strategies in sustainable poultry farming.