Objective To investigate the effect of long non-coding RNA (LncRNA) Hox transcript antisense inter-genic RNA ( HOTAIR ) on the cell proliferation and apoptosis of renal cancer cell lines 786-O and ACHN. Methods Small interfere RNA ( siRNA ) that aims to down-regulate HOTAIR expression was transfected into two renal cell lines respectively, and the transfection efficiency was evaluated by qRT-PCR. Then the MTT assay,Ho-chest staining assay and enzyme-linked immunosorbnent assay(ELISA) were used to detect cell proliferation and apoptosis. Results The expression of HOTAIR could be down-regulated effectively by the siRNA (P < 0. 05). Down-regulation of HOTAIR could inhibit the proliferation(P < 0. 05) and increase apoptosis(P < 0. 05) of two re-nal cancer cells. Conclusion HOTAIR plays a role in promoting cell growth of renal cancer.