Oo Na... Mahal Na Kung Mahal (lit. 'Yes... It's Loved If Loved') is a Filipino coming-of-age/romantic comedy film produced by Star Cinema that released on September 29, 1999. The film si directed by Johnny Manahan.

It features the soundtrack "Oo na Mahal na Kung Mahal Kita" performed by the band Frasco and later covered by Parokya ni Edgar (re-titling it as "Wag Mo Na Sana"). It was originally composed by Frasco members Francis Mortiz and Erwin Romulo, contrary to the popular belief that it was Chito Miranda.

• John Lloyd Cruz as Igi Boy
• Baron Geisler as Ivan
• Marc Solis as Enad
• Kaye Abad as Miles
• Kristine Hermosa as Chrissie
• Nikki Valdez as Sally

• Elizabeth Oropesa as Mely
• Ronaldo Valdez as Tito Paul
• Tommy Abuel as Col. Ruiz
• Bonggoy Manahan as Uncle Manny
• Manny Castañeda as Mr. Carpio
• Bibeth Orteza as Clara (Enad's mother)
• Yoyong Martirez as Luis (Enad's father)
• Miguel Dela Rosa as Noel (Enad's older brother)
• Gino Paul Guzman as Lino (Miles's older brother)

• Gary Lising as himself
• Bearwin Meily as Bearwin
• Patrick Garcia as Patrick
• Jodi Sta. Maria as Patrick's girl
• Tracy Vergel as Bearwin's girl 1
• Desiree del Valle as Bearwin's girl 2
• Bentong as himself (Col. Ruiz's ka-barkada)
• Boyong Baytion as Philip (Col. Ruiz's ka-barkada)
• Joji Isla as Bingo Master

• Oo Na... Mahal Na Kung Mahal at IMDb