Industrialization of the global market has brought about an organized approach to managing an organization that has experienced significant expansion. This has given the leadership of the company the insight to focus on sustainable growth and evolution that is sustainable while upholding control over internal procedures. Sustainability in leadership is an essential component of sustainable growth. In order to ensure sustainable development, board diversity has a significant effect on internal control and sustainable leadership. The current study consequently intended to investigate how sustainable leadership mediating affected the relationship between board diversity and the internal control prospect of Nepal. The quantitative data was gathered from 162 respondents from different corporate enterprises using a self-administered questionnaire. Partial least squares structural equation modeling (PLS-SEM) was used to analyze survey data. The findings indicate that internal control and board diversity are positively correlated. The result demonstrates that internal control is significantly impacted by sustainable leadership. The relationship between board diversity and internal control is mediated by sustainable leadership. According to the outcome, the purpose of accomplishing more ambitious future goals at an increased pace of sustainable growth, business entities should concentrate on sustainable leadership.