Gary O'Donnell may refer to:

• Gary O'Donnell (footballer) (born 1965), Australian Rules footballer and coach
• Gary O'Donnell (British Army soldier) (1968–2008), British recipient of the George Medal and bar
• Gary O'Donnell (Gaelic footballer) (born 1988), Gaelic football]] player

• Sir John Birchenough, 1st Baronet
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• Sir John Bruce-Hope, 7th Baronet
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