To assess the timing of root canal preparation and the quality of obturation after a single sitting pulpectomy in primary mandibular molars using manual and rotary equipment in young children between the ages of 4 and 8 year. Material and Method: In present study pulpectomy was performed on 40 primary mandibular. For half of them, hand K files were used, and for the other half, Pro AF baby gold rotary files were employed. The amount of time spent instrumenting, the quality of the obturation were documented. Result: It was observed that Pro AF baby gold offered the quality obturation and required less instrumentation time than hand file. Conclusion: In pulpectomies of primary teeth, pediatric rotary files are effective substitutes for hand instrumentation and can be regarded as the gold standard of therapy