One of the most important tools for lean production (LP) is value stream mapping (VSM), which identifies and reduces errors, losses, lead-time, and improves value creating time, thus enhances product quality through empowering production unit in terms of production risk and cost reduction in long term. This research aims at examining the effect of improvements identified through VSM on the overall equipment effectiveness (OEE) metric. In order to do so, a structured questionnaire was designed and employed. First of all, factors affecting VSM and OEE were assessed, the amount of conformity between theoretical results and actual results was analysed using current and future VSM and current and future values of OEE. Findings indicate that the OEE metric is positively and significantly influenced through identified improvements of VSM; therefore, studying and identifying improvement opportunities and also implementing changes and necessary adjustments will improve production process directly. Which due to lowering cost and enhancing quality, in turn, leads to higher customer satisfaction. Also, results show that the implementation of identified improvements through VSM will affect differently the measures of the OEE. Finally, some recommendations for improvement and several corrective measures for implementing LP within the surveyed plant are proposed.