Present research work was undertaken to estimate the genotype and environment interactions of 48 lentil genotypes across different environments, to identify the suitable genotypes for heat tolerance in lentil. Stability and adaptation through different stability parameters and performance traits of 48 lentil genotypes were studied. Genotypes IC201655 and IC201786 showed high seed yield and pods/plant stability. The genotype Asha recorded general adaptation showing above population mean for seed yield/plant, 100 seed weight and harvest index. Genotype Howrah local 2 recorded such trend for seed yield and harvest index. Howrah local 2 also recorded days to maturity close to population mean. Genotype North 24 Parganas local recorded such trend for harvest index and 100 seed weight (above population mean) and days to maturity (below population mean). Genotype IC201710 would likely to perform well under favourable situation for seed yield/plant, pods/plant and harvest index. Correlation among stability estimate revealed that there were high significant correlations between seed yield and pods per plant. Therefore if pods per plant are stable then seed yield will also be stable. These findings can be very useful in lentil breeding programme related to heat tolerance.(based on what?).