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The plant hormone ABA regulates various physiological processes, such as promoting stomatal closure and inhibiting hypocotyl elongation by mediating de-phosphorylation of H⁺-ATPase. However, the mechanism acting on ABA-induced de-phosphorylation of H⁺-ATPase remains largely unknown. <i>SMALL AUXIN UP RNAs</i> (<i>SAURs</i>), the largest family of early auxin-response genes, were well-reported to bind to and inhibit PP2C.D phosphatases to maintain plasma membrane H⁺-ATPase activity. In this study, we aimed to investigate whether SAUR-PP2C.D functional modules were involved in ABA-mediated inhibition of hypocotyl elongation. Here, we show that ABA suppresses hypocotyl elongation in both light-grown and dark-grown tomato seedlings in a dose-dependent manner. Hypocotyl elongation of dark-grown seedlings was more sensitive to ABA compared to that of light-grown seedlings. ABA upregulates seven <i>SlPP2C.D</i> genes. <i>SlPP2C.D1</i> was highly expressed in hypocotyl and upregulated by light. Y2H data showed <i>SlPP2C.D1</i> interacted with SlSAUR2, 35, 40, 55, 57, 59, 65, and 70. The other four SlPP2C.Ds were also associated with a subset of SAUR proteins. Our findings have provided new insights for further examination on the SAUR-PP2C.D modules that regulate outputs of ABA and other phytohormones controlling plant growth and development.