Ethylene-induced ripening is a highly efficient strategy for the postharvest ripening of mangoes. Although ethephon is widely adopted as a conventional ripening agent, research pertaining to gaseous ethylene for this application remains scarce. Herein, Keitt mangoes were used as experimental model and were maintained in an atmosphere-controlled chamber with 100 μL•L-1 ethylene or in an ethylene-free environment for 48 h. Samples were collected regularly and assessed concerning fruit firmness, soluble solids content (SSC), starch content, respiratory rate, malondialdehyde (MDA) content, peroxidase (POD) activity, color changes, and volatile compounds. In comparison with the control group, ethylene gas treatment exerted a significant regulatory effect on the postharvest physiology and quality attributes of Keitt mangoes. Specifically, it expedited the rapid yellowing of fruit peel and the quick darkening of pulp color. At day 4 of storage, fruit firmness decreased significantly by 70.44% relative to the control group (P<0.05); at day 6, the SSC of the ethylene-treated group had increased significantly by 12.14% compared with the control group (P<0.05); and at day 8, the starch content of the ethylene-treated group had decreased significantly by 8.8% compared with the control group, alongside with more rapid MDA accumulation. Electronic nose analysis showed higher contents of organosulfur and methyl-containing compounds, as well as of nitrogen oxides in the ethylene-treated group at days 4 and 8, whereas the control group had a higher content of aromatic-alkyl compounds at day 4, which enabled effective distinction of flavor differences between the two groups. Hence, ethylene gas treatment can accelerate the postharvest ripening of Keitt mangoes and improve fruit quality, providing a scientific basis and technical reference for the postharvest ripening and preservation of Sichuan Keitt mangoes.