The study sought to identify the trends in Medical professionals’ use of different types of information resources, particularly electronic resources, to develop their teaching, ongoing research activities, and their own personal knowledge at National Medical Library (NML). The problem has been studied based on the information available in the open literature and a survey conducted on the usage patterns, interaction and impact of EIS on medical professionals at National Medical Library (NML) for the year 2010-2011. A well structured 200 questionnaires distributed for the collection of primary data. Valid 193 questionnaires collected and analyzed. The result showed a growing interest in EIS among the users at NML. The survey showed that majority of respondents marked that library possessed useful EIS for the medical community. Awareness among the users about the availability and preference of EIS was found highly satisfactory. Majority of the respondents (100%) use journals of Cengage Learning and journals from Royal Society of Medicine Press. Electronic Information Resources were mostly used for research needs and highly impact on research. The EIS is better for accessing current & Comprehensive information. 100% marked to a very high extent electronic resources have become a substitute for printed materials. The Library needs to undertake a review to identify other databases that may be needed, to promote the use of e-resources in teaching and learning, and to develop the search skills of faculty and students.