Gassner is a surname. Notable people with the surname include:
Alexander Gassner (born 1989), German skeleton racer Dennis Gassner (born 1948), Canadian production designer Hermann Gassner (born 1988), German rally driver Louis Gassner (born 1945), Liechtenstein politician Peter Gassner (born 1965), American billionaire businessman Roman Gassner (1929–2008), Liechtenstein politician Sebastian Gassner (born 1987), Liechtenstein politician