The current study examined the role of natural mentoring relationships in the academic performance of urban, diverse, Latino high school students. Participants reported up to three mentors in their lives, and they were asked about their mentors' demographic characteristics and the characteristics of their mentoring relationships. The presence of a mentor was associated with fewer absences, higher educational expectations, and greater expectancies for success and sense of school belonging. Further, the number of reported mentors predicted fewer absences, higher educational expectations and a greater sense of school belonging. Mentors' educational level, frequency of contact, relationship duration, and total form of support provided by mentors were related to participants' academic outcomes. Mentor type also made a difference in youth's academic outcomes. Implications for future mentoring research and programs are discussed. (Contains 3 tables and 2 footnotes.)