Cadmium (Cd) is a heavy metal that can have toxic effects on plants even in trace amounts in the soil. In this study, we aimed to elucidate the role of exogenous O-(2-naphthylsulfonyl)oxime (ANSO) in maize plants under Cd stress. For this purpose, the following experimental groups were formed: The control group will be kept in distilled water for 18 hours, the second group will be kept in ANSO (0.3 mM) for 6 hours and then in distilled water for 12 hours, the third group will be in distilled water for 6 hours and then in Cd solution (100 μM) for 12 hours, fourth group ANSO (0.3 mM) for 6 hours, followed by 12 hours of Cd solution (100 µM). When ANSO+Cd application is compared to Cd, the Cd content increased 7.8 times, while the ABA content decreased. RWC content, which was reduced by Cd stress, was not changed by ANSO pre-treatment. Chlorophyll content, which decreased with Cd treatment, increased with ANSO+Cd treatment. While the carotenoid content increased with Cd application, it increased much with ANSO+Cd application. The H2O2 content and lipid peroxidation increased in the plant with Cd stress and decreased with ANSO pre-treatment. With ANSO+Cd treatment, GPX activity decreased compared to Cd treatment, but CAT and APX values increased. ANSO pre-treatment did not significantly change SOD activity. Cd application increased proline content compared to control, but proline content decreased compared to Cd with ANSO pre-treatment. In ANSO+CD application, ascorbic acid, cinnamic acid and catechol values increased compared to the values in plants treated with Cd alone, but the trans-coumaric acid value decreased. As a result, it can be said that ANSO pre-application to maize seedlings under Cd stress provides the preservation of the ion balance of the cells by chelating Cd+2 ions in the cell wall and vacuoles.