Aberrant long-noncoding RNA (lncRNA) expression has been shown to be involved in the pathogenesis of endometrial cancer (EC). Herein, we report a novel tumor suppressor lncRNA SOCS2-AS1 in EC. Quantitative real-time PCR was performed to detect RNA expression. In situ hybridization and nuclear/cytoplasmic fractionation assays were used to detect the subcellular location. We found that SOCS2-AS1 was downregulated in EC tissues. Its reduced expression was correlated with advanced clinical stage and poor prognosis. Forced expression of SOCS2-AS1 suppressed EC cell proliferation and induced cell-cycle arrest and apoptosis. SOCS2-AS1-binding proteins were detected using RNA pull-down assay and mass spectrometry. Mechanistically, SOCS2-AS1 bound to Aurora kinase A (AURKA) and increased its degradation through the ubiquitin-proteasome pathway. In conclusion, SOCS2-AS1 may thus serve as a prognostic predictor and a biomarker for AURKA-inhibitor treatment in EC patients.