This paper gives a method for estimating the viscosity of crude petroleum by combining state equations with improved Dean Stiel viscosity model The best equation for the estimation is Patel Teja equation with an average relative error of 6 27%

• 基于改进的Dean－Stiel粘度模型，提出了将状态方程与之结合进行原油粘度预测的方法，采用Patel－Teja状态方程预测结果最好，平均相对误差为6.；27%25。