IMNCI is a key evidence based strategy for reducing neonatal and infant mortality through systematic approach. The focus is on overall well being of the child. The aim of IMNCI is to train, and provide preventative and home-based care through, India’s network of frontline health workers and supervisors. ASHA occupies a major position and perform as important element in health system networking. Supportive supervision and timely monitoring of any program is of utmost importance to make the program a success. Objective: To assess the impact of monitoring and supportive supervision on performance of IMNCI trained ASHA. Method: The present study is a longitudinal study of Baran district of Rajasthan, India. A total number of 382 IMNCI trained ASHAs selected by random sampling technique. An interview schedule was used for collection of data regarding the skills of ASHA, the health worker for her skills on IMNCI protocol with respect to skill in identifying the sick child, grade him, and refer him/her if required and on recording and reporting of the program. Data analysis was done using SPSS 16.0. Results: The improvement in the overall IMNCI skills from visit first to third visit was highly significant statistically. Conclusion: Close monitoring, supportive supervision and re-strengthening of the program had a positive impact on the overall performance of ASHAs.