This study has covered a vast area of research in natural ventilation, CFD modelling, and thermal comfort. It investigates the thermal comfort of a naturally ventilated hostel building in the composite climate of Jaipur, India using CFD simulation tool 'Cradle scSTREAM'. The objective of the study is to analyze the effectiveness of natural ventilation strategies and to assess the results based on thermal comfort inside the building with the help of CFD. The current study obtains the airflow pattern and evaluate the thermal comfort. A 3-Dimensional model has been developed to analyze the effect of indoor environmental condition i.e. indoor airflow and temperature of the room to evaluate thermal comfort. The field study was carried out to collect the data of boundary conditions for CFD simulation. The CFD model has also been validated with the experimental data, which shows an acceptable accuracy between simulation results & experimented measurements. Further, the parametric study of cross ventilation and night ventilation has been performed to enhance the thermal comfort in the building.