Objective To investigate the expressions of aldehyde dehydrogenase 1(ALDH1), hypoxia-inducible factor 1α(HIF-1α), vascular endothelial growth factor (VEGF) in laryngeal squamous cell carcinoma(LSCC) and their relationships with clinical significance. Methods In situ hybridization (ISH) method and immuohistochemical staining were used to detect the mRNA and protein expressions of ALDH1，HIF-1α and VEGF in 120 LSCC specimens and 60 cases of normal laryngeal tissue．Their relationships with clinical pathological parameters were analyzed. Results The positive rates of ALDH1，HIF-1α and VEGF mRNA in LSCC were 57.5％（69/120）, 73.3％（88/120）, 56.7% （68/120）, while the positive rates of proteins were 55.8％（67/120）,70.8％（85/120） and 55.0% （66/120）, respectively. which were significantly higher than those in controls（PPPPP
