The CROPGRO-pigeonpea model embedded in DSSAT v4.7.5 was used to assess the impact of climate change on phenology and grain yield of reference genotype of different pigeonpea maturity groups. The impact of climate change delayed reproductive stages (anthesis, maturity) and decreased grain yield of reference genotype of different pigeonpea maturity groups were evident in all scenarios. Short duration genotypes (MN5, ICPL88039, Prabhat, UPAS120) showed progressively higher decrease in yield as compared to medium (Maruti, Asha, ICP7035) and long (Bahar, MAL13) duration genotypes with each successive increase in scenatio from RCP2.6 to RCP8.5 and projected year from 2010 to 2095. Anthesis was delayed 9 days in MN5 to 20 days in Bahar and maturity delayed 15 days in MN5 to 24 days in Bahar with RCP 8.5 in year 2095 in comparison to RCP2.6 in years 2010, whereas, grain yield was decreased 14% in Bahar to 66% in MN5 among genotypes of different maturity groups.