Long non-coding RNAs (lncRNAs) have been regarded as promising biomarkers in the regulation of various biological and pathological processes of non-small cell lung cancer (NSCLC). LncRNAITGA9-AS1 has been reported to be down-regulated in elderly patients with lung cancer, but how it may influence NSCLC remains to be identified. Therefore, we aim to explore the specific mechanism involving ITGA9-AS1 and ITGA9 in NSCLC. A functional assay was conducted to verify ITGA9-AS1's proliferative effects on NSCLC cells. Mechanism experiments with bioinformatics predictions were performed to explore the interaction of ITGA9-AS1 and ITGA9 in NSCLC cells. ITGA9-AS1 inhibited NSCLC cell proliferation while enhancing cell apoptosis. It up-regulated ITGA9 by competitively sponging miR-4765, and it stabilizedITGA9 mRNA by recruiting a RNA-binding protein (RBP)-HNRNPU (heterogeneous nuclear ribonucleoprotein U) in NSCLC cells. ITGA9-AS1 suppressed NSCLC progression by the up-regulation of ITGA9 via targeting miR-4765 and recruiting HNRNPU.