OBJECTIVE: Tongue squamous cell carcinoma (TSCC) is a prominent type of oral cancer. Despite the numerous research studies on SCC and microRNAs (miRs), the relation between TSCC and miR-135b-5p is poorly discussed. This experiment aims to find out the possible effect of miR-135b-5p on TSCC with the network of its downstream genes. STUDY DESIGN: TSCC tissues and adjacent normal tissues were harvested. Then, expression of miR-135b-5p and AT-rich interactive domain-containing protein 1A gene (ARID1A) and the phosphatidyl inositol 3-kinase/protein kinase B (PI3K/AKT) pathway was analyzed. After the transfection of miR-135b-5p inhibitor and its negative control into TSCC cells, functional assays were employed to measure cell proliferation, apoptosis, and cycle. Next, the target relation between miR-135b-5p and ARID1A was confirmed. In addition, the fact that miR-135b-5p promoted TSCC development via mediating ARID1A was demonstrated by functional rescue experiment. RESULTS: miR-135b-5p was upregulated in TSCC tissues and cells, while ARID1A was suppressed (p< 0.05). Silenced miR-135b-5p discouraged TSCC cell proliferation, improved apoptosis, induced cell cycle arrest, and increased ARID1A expression while inactivating the PI3K/AKT axis (p<0.05). Furthermore, knockdown of ARID1A reversed the impacts on TSCC cell proliferation and apoptosis exerted by silencing miR-135b-5p. CONCLUSION: This research supported that silenced miR-135b-5p impeded TSCC proliferation and apoptosis by promoting ARID1A and inactivating the PI3K/AKT axis, which may provide some indications for TSCC alleviation. © Science Printers and Publishers, Inc.