

Introduction
Mariano de Leon (born November 18, 1958), known by his stage name Julio Diaz, is a Filipino film and television actor in the Philippines. Diaz is of Filipino Mexican background. He received the Best Actor Gawad Urian Award nomination for his performance in Takaw Tukso (1986).
Career
Diaz did movies such as Sinner or Saint (1984) with Claudia Zobel, Paano Tatakasan ang Bukas? (1988) with Dina Bonnevie, Kailan Ka Magiging Akin? (1990) with Janice de Belen, Aliwan Paradise (1992), Bayani (1992), Sakay (1993) with Tetchie Agbayani, The Flor Contemplacion Story (1995) with Nora Aunor, Segurista (1996) with Michelle Aldana, Sana Pag-ibig Na (1998) with Angel Aquino, Hubad Sa Ilalim Ng Buwan (2000) with Klaudia Koronel, Balahibong Pusa (2001) with Rica Peralejo, and Lapu-Lapu (2002) with Lito Lapid.
He also appeared in films like Batanes (2007) with Iza Calzado, Serbis (2008) with Gina Pareño, Kinatay (2009) with Coco Martin, Biyaheng Lupa (2009) with Jacklyn Jose, and 24K (2009).
Awards and nominations
- 2011 Best Supporting Actor Nominated Gawad Urian Award Blood Ties (2010)
- 2010 Best Male Performance Nominated YCC Award Soliloquy (2009)
- 2009 Best Supporting Actor Nominated Gawad Urian Award Service (2008)
- 1994 Best Actor Nominated FAMAS Award Sakay (1993)
- 1993 Best Actor Nominated FAMAS Award Bayani (1992)
- 1993 Best Actor Nominated Gawad Urian Award Bayani (1992)
- 1987 Best Actor Nominated Gawad Urian Award Takaw Tukso (1986)