To uncover the effect of miR-181a-5p regulating large tumor suppressor 2 (LATS2) in biologic processes of adenoid cystic carcinoma (ACC) cells, miR-181a-5p and LATS2 expression in lacrimal ACC (LACC) tissues were assessed. The ACC cell lines were respectively treated with altered miR-181a-5p or LATS2 to determine the biologic functions in ACC cells. Binding ability of miR-181a-5p and LATS2 was confirmed. Tumor growth in vivo was assessed as well. MiR-181a-5p was upregulated while LATS2 was downregulated in LACC tissues. Reduced miR-181a-5p restrained malignant phenotype of ACC cells and decelerated xenograft growth. Conversely, LATS2 reduction had opposite effects compared to miR-181a-5p knockdown on ACC cells. Furthermore, downregulated LATS2 could abolish the alterations in ACC cells induced by miR-181a-5p silencing. MiR-181a-5p inhibition upregulated LATS2 to suppress malignant behavior of ACC cells in vivo and in vitro .