The aim of the present study was to identify the function of long non-coding RNA (lncRNA) small nucleolar RNA host gene 3 (SNHG3) and examine its effects on non-small cell lung cancer (NSCLC). A series of in vitro experiments were employed to evaluate the effects of SNHG3 on the progression of NSCLC, including Cell Counting Kit-8, 5-Ethynyl-2′-deoxyuridine, flow cytometry, wound healing, Transwell, western blotting and reverse transcription-quantitative PCR assays. Bioinformatics analyses and a luciferase reporter assay were performed to identify the target gene of SNHG3 and microRNA (miR)-1343-3p. Finally, recuse experiments were conducted to verify the effect of SNHG3 and its target gene on proliferation, apoptosis, migration and invasion. The findings indicated that lncRNA SNHG3 was highly expressed in NSCLC tissues and cell lines. Knockdown of lncRNA SNHG3 inhibited cell proliferation, migration and invasion, and accelerated cell apoptosis in NSCLC cell lines. The results of the bioinformatics analysis and the luciferase reporter assay indicated that lncRNA SNHG3 directly bound to miR-1343-3p and that it could downregulate the expression levels of miR-1343-3p to promote the progression of NSCLC. Rescue experiments indicated that lncRNA SNHG3 increased nuclear factor IX (NFIX) expression by sequestering miR-1343-3p in NSCLC. These results suggested that the SNHG3/miR-1343-3p/NFIX axis may serve as a novel prognostic biomarker and therapeutic target for NSCLC.