Abstract: Colletotrichum gloeosporioides was treated with different concentrations of β-aminobutyric acid (BABA) to investigate the inhibitory activity of BABA against C. gloeosporioides and to determine the effects of spraying mango fruit with an appropriate concentration of BABA on fruit texture, quality, and appearance during storage. The results of the antifungal assay showed that, in the 50 mmol·L⁻¹ treatment group, the spore germination rate was only 37.67% after 48 h of incubation, and the inhibition rate of mycelial growth reached 79.64% after 72 h, indicating that this concentration of BABA effectively inhibited the growth and reproduction of C. gloeosporioides. The storage experiment showed that spraying mango fruit with 50 mmol·L⁻¹ BABA reduced the natural incidence of disease by 53.34 percentage points and the weight loss rate by 9.6 percentage points. In addition, it inhibited fruit yellowing, delayed the decreases in firmness and titratable acidity, postponed the increase in soluble solids content, and effectively extended the shelf life of mangoes to 24 days.