Baron Frederick von Geisler (Tagalog: ; born 5 June 1982 in Clark Air Base, Angeles City, Philippines), also known simply by his on-screen name as Baron Geisler, is a Filipino actor, businessman, occasional model, resource speaker, amateur artist and aspiring poet.
As a child actor and later as a teen idol, Geisler's career has been characterized by critical and popular notoriety followed by a period of alcohol abuse and legal troubles, before a resumption of critical repute and resurgence of commercial success in middle age. Several of Geisler's accolades includes winning the Best Actor award in the 4th Cinemalaya Independent Film Festival on July 20, 2008 and the 2005 PMPC Best Single Performance of an Actor in Maalaala Mo Kaya ("Would You Remember?").
Geisler was born to Gracia Bayonito of Bicol, Philippines and Donald David Geisler Jr., a German American who was stationed at the former U.S. military base in Angeles City. His older brother is Olympian Donald Geisler.