In the study, three benzimidazolate-based Cu²⁺ complexes were identified as SOD1 mimics to explore their effects on the levels of reactive oxygen species (ROS) and activities of antioxidant enzymes in drought-stressed rice organs. Superoxide dismutase (SOD) activity of the mimics was found to be controlled by unsaturated coordination, auxiliary ligands, and counter-anions. In comparison to the control, SOD1 mimic treatment for rice seeds significantly reduced ROS (O₂•⁻, H₂O₂, and •OH) levels in the rice leaf and root while notably increased activities of antioxidant enzymes, including SOD1 and catalase. It can enhance the tolerance of plant organs to drought stress and, thus, has a practical potency of application in rice production on arid land.