Self-controlled experiment research has been made on 80 selected hospitalized patients at random. We have compared the blood pressure of supine position, left lateral position, right lateral position dorsal artery of foot blood pressure and supine position brachial blood pressure to study the impact of different lying position on foot blood pressure and the relationship between the blood pressure and supine position brachial blood pressure. We conclude that the differences among the three lying position foot blood pressure has no statistical significance. The systolic pressure and the diastolic blood pressure （P〈0.01） of foot blood pressure is obviously higher than that of supine position brachial blood pressure. The systolic pressure and the diastolic blood pressure（P〈0.01） of foot blood pressure and supine position brachial blood pressure exhibit positive linear correlation. Regression equations are： Y=29.76＋0.64X（R^2=0.67） ;Y=15.38＋0.73X （R^2=0.52）