Purpose: Esophageal squamous cell carcinoma (ESCC) is one of the most malignant cancers with poor survival rate in the world. In this study, effects of novel circular RNA hsa_circ_0000977 in ESCC were investigated in order to find its pathophysiology characteristics and roles. The expression of hsa_circ_0000977 was measured in both ESCC and matched para-carcinoma tissues by real-time PCR, and then the binding site of hsa_circ_0000977 to miRNA was identified with a Luciferase reporter. Subsequently the effects of hsa_circ_0000977 on cell proliferation were analyzed using Cell Counting Kit-8, and cell apoptosis was observed by flow cytometry and Western blot after a silence of hsa_circ_0000977 expression on both KYSE150 and KYSE180 cells. Results of this study showed that hsa_circ_0000977 was significantly overexpressed in ESCC tissues/cells when compared with normal esophageal tissues/cells. Hsa-miR-874 targeted hsa_circ_0000977 was identified and both abnormally existed in ESCC tissues/cells. In addition, the ESCC cells without special siRNA treatment were compared: cell proliferation was decreased; cell apoptosis was enhanced; and expressive levels of p53, Caspase-3, and ratio of Bax/Bcl-2 were augmented post transfecting with siRNA-hsa_circ_0000977 in both of KYSE150 and KYSE180 cells. Taken together, the novel data indicated that hsa_circ_0000977 might have potential ability to regulate ESCC development. (Am J Transl Med 2019. 3:85-95).