Drought is a major factor restricting the production of rice (Oryza sativa L.). The identification of natural variants for drought stress-related genes is an important step toward developing genetically improved rice varieties. Here, we characterized a member of the SQUAMOSA PROMOTER BINDING PROTEIN-LIKE (SPL) family, OsSPL10, as a transcription factor involved in the regulation of drought tolerance in rice. OsSPL10 appears to play a vital role in drought tolerance by controlling ROS production and stomatal movements. Haplotype and allele frequency analyses of OsSPL10 indicated that most upland rice and improved lowland rice varieties harbor the OsSPL10 Hap1 allele, while the OsSPL10 Hap2 allele was mainly present in lowland and landrace rice varieties. Importantly, we demonstrated that the varieties with the OsSPL10 Hap1 allele show low expression levels of OsSPL10 and its downstream gene, OsNAC2, which decreases the expression of OsAP37 and increases the expression of OsCOX11, thus preventing ROS accumulation and PCD. Furthermore, knockdown or knockout of OsSPL10 induces fast stomatal closure and prevents water loss, thereby improving drought tolerance in rice. Based on these observations, we propose that OsSPL10 confers drought tolerance by regulating OsNAC2 expression and that OsSPL10 Hap1 could be a valuable haplotype for genetic improvement of drought tolerance in rice. This article is protected by copyright. All rights reserved.