Purpose: As businesses continue to forge ahead in the twenty-first century, knowledge management (KM) has materialized as a significant differentiator. The process of creating new knowledge, sharing, and preserving such knowledge, is crucial for achieving competitive advantage. To gain maximum benefit from new knowledge, it must be efficiently integrated into the organization within a continuous knowledge life cycle. In this respect, mentoring is becoming ever more effective as a means to facilitate knowledge creation and sharing and build intellectual capital. This study aims to examine how both formal and informal mentoring enhances KM in the Lebanese banking sector. Design/methodology/approach: Professionals in the Lebanese banking sector were surveyed to measure their perception of the impact of mentoring on their willingness to share information within the organization on both a formal and informal basis. A Pearson correlation was conducted to test the hypotheses. Findings: Results suggest that informal mentoring is highly correlated with KM; whereby the more employees practice mentoring willingly the more knowledge will be shared, preserved, and used within the organization. However, there was little support for formal mentoring. Practical implications: The results suggest that management should be highly supportive of informal mentoring as a means to capture and retain organizational knowledge. They should design and reward informal mentoring processes within the organization. Originality/value: This paper adds to the existing mentoring literature by empirically testing the relationship between mentoring and KM.