Objective To investigate whether microRNA-30e-5p (miR-30e-5p) can inhibit tumor growth by down-regulating the expression of ubiquitin-specific protease 22 (USP22) in non-small cell lung cancer (NSCLC). Methods We detected the expressions of miR-30e-5p and USP22 in NSCLC tissues and adjacent non-tumor tissues by qPCR, Western blotting, and immunohistochemistry. After transfecting with miR-30e-5p mimic or miR-30e-5p inhibitor, the expressions of miR-30e-5p and USP22 in H460 cells was detected by qPCR and Western blotting. USP22 mutant vector was constructed and used to identify miR-30e-5p binding sites in the USP22 gene by luciferase reporter assay. The proliferation of H460 cells was measured in vitro by MTT assay and the tumor growth in nude mice was measured in vivo by xenograft assay. The cell cycle arrest and apoptosis of H460 cells were detected by flow cytometry. Results The expressions of MiR-30e-5p and USP22 in NSCLC tissues were significantly higher than those in adjacent non-tumor tissues (both P<0.01). Overexpression of miR-30e-5p significantly down-regulated the expressions of USP22 mRNA and protein in NSCLC tissues (both P<0.01), while inhibition of miR-30e-5p expression significantly up-regulated the expressions of USP22 mRNA and protein (both P<0.01). MiR-30e-5p was negatively related to USP22 in NSCLC tissues (P<0.01). MiR-30e-5p could negatively regulate the expression of USP22 by binding to the specific sequence of 3'UTR. Overexpression of miR-30e-5p significantly inhibited proliferation of H460 cells, induced cell cycle arrest and apoptosis, and inhibited tumor growth in nude mice (P<0.05, P<0.01); while inhibition of miR-30e-5p significantly promoted the cell proliferation and inhibited cell cycle arrest and apoptosis (P<0.05, P<0.01). Conclusion MiR-30e-5p can down-regulate the expression of USP22, thereby inhibiting the development and progression of NSCLC, suggesting that it can be used as a potential therapeutic target for NSCLC.