Abstract: Objective To detect the expression of histone deacetylase 1（HDAC1），HDAC5 and E-cadherin in lung adenocarcinoma tissue and analyze their correlation. Methods The expression of HDAC1，HDAC5 and E-cadherin in 93 cases of lung adenocarcinoma and 48 adjacent tissues was detected by immunohistochemical SP method. The relationship between the protein expression and clinicopathological characteristics，and the correlation among the three proteins were analyzed. Results The positive rate of HDAC1 expression in lung adenocarcinoma was 58.06％，which was higher than that in adjacent tissues（20.83%），and the difference was statistically significant（P＜0.05）. The positive expression rates of HDAC5 and E-cadherin in the adjacent tissues were 66.67％ and 68.75％，which were higher than those of lung adenocarcinoma tissues（48.39% and 45.16%）, and the difference was statistically significant（P＜0.05）. The expression of HDAC1 and E-cadherin was correlated with age（P＜0.05），and the expression of E-cadherin was related to the degree of differentiation （P＜0.05）. The expression of HDAC5 was not correlated with clinicopathological characteristics（P＞0.05）. HDAC1 was negatively correlated with HDAC5 and E-cadherin（r=-0.224, r=-0.236，P＜0.05）. There was no significant correlation between HDAC5 and E-cadherin（r=0.159，P＞0.05）. Conclusion The expression of HDAC1，HDAC5 and E-cadherin in lung adenocarcinoma tissue suggested that there was a certain relationship among the three proteins，and the combined detection of the three proteins may be helpful to predict the prognosis and select the drug reasonably.