The Indian Summer Monsoon (ISM) plays a very important role in Indian agriculture and India&rsquos  socio-economic conditions. However, there is a large spread in the ISM projections of future  climate by the end of 21st century. Evaluation of ISM rainfall (ISMR) changes during past warm  periods could help us in a better understanding of ISMR variability in the future. Therefore, to  study the ISMR variability, we have chosen one of the recent warm periods having similar global surface temperature and orbital forcing, such as solar luminosity as projected by the end of the 21st century, which is mid-Pliocene (~3.2 Ma). For investigation of ISMR conditions in midPliocene, we have used the available models from Coupled Model Intercomparison Project phase 6 (CMIP6) CESM, EC, GISS, HadGEM, NorESM and IPSL. During the mid-Pliocene, we find  an increase in the JJAS rainfall over most parts of India in comparison to the pre-industrial  period, with an increase of 34% in seasonal precipitation. This higher precipitation conditions  during the mid-Pliocene is accompanied by thermo dynamical (higher Carbon Dioxide (CO2)  forcing led to higher tropospheric temperature and higher precipitable water) and dynamical  (larger tropospheric temperature gradient between Indian landmass and southern Indian Ocean  corresponds to enhanced moisture transport, enhanced low-level cross-equatorial flow and  intensified Monsoon Hadley Circulation) aspects. Further, interannual variations in ISMR are simulated to be less during the mid-Pliocene relative to the pre-industrial period from the statistical analysis of the coefficient of variation in precipitation anomaly and standard deviation in different monsoon indices from all model simulations. The interannual variations in sea surface temperature of different Oceans like Pacific, Indian and North Atlantic are also found to be less. However, the teleconnection of ISMR is found to be stronger with ENSO only during the mid-Pliocene as compared to pre-industrial period and insignificant with other oceans&rsquo forcing. The change in the ISM mean state in the future period (2071-2100 using SSP5-8.5 scenario with respect to the historical 1985-2014) in comparison with analogous past period (mid-Pliocene  with respect to the pre-industrial) is found to be slightly less. By the end of the 21st century, the projected ISM rainfall increase is dominated by thermodynamic components driven by the extent  of warming over the Indian region rather than the large scale monsoon circulation.