γ-Aminobutyric acid (GABA), an endogenous amino acid widely found in living organisms, has important functions in plants such as regulating growth and development, maintaining carbon and nitrogen nutrient balance, and coping with adversity. In this study, we investigated the effects of exogenous 0.5 mmol/L GABA on the growth, antioxidant metabolism, and GABA shunt metabolism of tall fescue under 20 μmol/L Cd stress, using tall fescue (