This research seeks to obtain thorough sympathetic of learning's contribution to a firm's competitiveness by analyzing how organizational learning (OL), implied as a dynamic capability, designs firms' strategic flexibility and competitive strategy performing to improve customer, financial, and market-related performance. This paper suggests that OL acts as a sign of a firm's capability to conform to developing market conditions (strategic flexibility), and that OL and flexibility at the same time encourage the performing of discrimination and cost-leadership strategies. This strategic conduct permits firms to reduce costs without harmful discrimination levels, and to improve customer and business performance. The study activates structural equation modeling (SEM) to evaluate the links that the research model describes. Data analysis follows from a sample of 362 medium-sized Iranian manufacturing firms. The results confirm the expected relationships and show OL to be an important instrument in modern markets to furnish customer value and to improve organizational performance by ways of effective competitive strategy design and flexible structure to rapid market development.