Stability of 42 genotypes of blackgram (Vigna mungo was conducted for grain yield at four different environments created by different sowing dates and seasons at Hisar. The most commonly used stability parameters like bi, S2di, σ2, S2xi and CV1 were employed. Significance of main environmental and interaction effects indicated the differential response of the genotypes to changing environments. The likely areas of adaptation of genotypes were identified. The genotypes, namely IPU-97-10, UH94–10 and DPU-91-5, though low yielder, were identified for general growing conditions due to average stability. These are likely to give some assured yield.