MGA can be an abbreviation of:

• Malaysian Golf Association
• Massachusetts Golf Association
• Matrox Electronic Systems Ltd
• Melengestrol Acetate - a contraceptive used on cattle
• Metal Gear Acid - a PlayStation Portable video game by Konami
• Metropolitan Golf Association of New York
• Minnesota Golf Association
• Minnesota Grocers Association
• Monongahela Railway
• Mounted Games Association
• Myasthenia Gravis Association

MGA can also refer to the MG A, a popular British sports car manufactured between 1955 and 1962 by MG, part of the Morris Motor Company.