Based on the growing significance of sustainable construction in the realization of sustainable development goals, this study investigates the perceived relationship between leadership practices and the success of sustainable construction projects in Iran. Adopting a mixed‐methods design and a cross‑sectional survey of leaders and professionals involved in construction projects in Tehran, data were collected using a structured questionnaire grounded in the Four‑Factor Leadership Model and analyzed through descriptive statistics, the Friedman test, correlation analysis, and simple linear regression. In addition, thematic content analysis was employed to identify key environmental and organizational challenges. The empirical results indicate that the most critical project management challenges in sustainable construction include managing remote and geographically dispersed teams, maintaining team cohesion, and addressing delays and cost overruns. In the Iranian context, traditional project success criteria (cost, time, and quality) remain predominant, while sustainability‑related performance indicators receive only moderate attention. With respect to leadership practices, “effective communication,” “clear goal setting,” and “leading by example” emerged as the most salient behaviors, whereas “building and developing stakeholder relationships” was ranked lowest in importance, suggesting cultural and organizational specificities relative to findings reported in some international studies. Regression analysis confirms that the perceived importance attributed to leadership practices constitutes a significant predictor of perceived project success in sustainable construction. By offering novel empirical evidence from Iran, this study underscores the critical role of enhancing communication, motivational, goal‑setting, and visionary competencies in leadership development programs. It further highlights the need to adapt leadership approaches to evolving working conditions particularly the management of distributed teams and to broaden the adoption of digital technologies in project management processes.