Floods are the most prevailing and catastrophic event that causes many causalities and a heavy toll on human lives and geological damage to the topology. Floods cannot be stopped completely, but their effect can be minimized by proper flood mitigation practices. Flood inundation modeling is one of the most exquisite non-structural measures for mitigating the effects of floods, although it is difficult in developing nations due to data scarcity. This study developed one-dimensional hydrodynamic models for the 178 km length of Krishna River and its tributary Bhima River, India, to perform the flood inundation simulation. MIKE Hydro River model and HEC-RAS model are employed in the study to compare the flood inundation modeling capabilities of the models. Freely available digital elevation models (DEM) of 30 m resolution are incorporated into the study to extract the geometry and cross-sections of the Krishna and Bhima Rivers. The 1D models are calibrated for the 2006 flood event and subsequently used for validation for the year 2009 flood. The performance of both models is assessed through statistical parameters like Correlation coefficient (CC), Root mean square error (RMSE), Index of agreement (d), and Percentage deviation in peak (%). The simulated water level obtained using the MIKE Hydro River model is in reasonable agreement with the observed values as indicated by the performance parameters.