Medical libraries play a very active role in quenching the information thirst of their users. Library users of medical libraries are life savers. The focus of this study is on the impact of medical libraries on clinical decisions of the medical practitioners in Pakistan. Quantitative research approach was used to undergo the study. Journals were reported as the most used library resources in the medical libraries under study. Medical literature placed in these libraries have a great impact on the clinical decisions of the medical doctors working in hospitals of Khyber Pakhtunkhwa, Pakistan. Provision of latest, relevant and sufficient medical literature to the libraries of these medical libraries is the cry of the day.