Garry Thomas Knapp (born 1947) was a New Zealand politician of the Social Credit Party.
He became Member of Parliament for East Coast Bays in 1980 when he defeated National candidate Don Brash in the 1980 by-election caused by the resignation of the sitting National MP. Knapp joined Bruce Beetham in parliament, where they both had high profiles.
In the 1984 election, while Beetham lost Rangitikei to a National Party challenger, Knapp retained East Coast Bays, and another Social Credit candidate, Neil Morrison, won Pakuranga. But in the 1987 election Knapp and Morrison were both defeated by National candidates, see Social Credit Party (New Zealand). Knapp also stood in the 1990 election