Abstarct: Improving drilling fluid properties as an important factor in increasing the efficiency of drilling operations have been considered. On the other hand, in the horizontal and directional drilling, friction cause increasing of torque and well unsteadiness in from of Bit Balling, Dog Leg, Key Seat. One way to reduce this friction is the lubrication of drilling mud. One ways to improve the properties of this drilling mud is, lubricating it with minimal impact on the rheology. The main objective of this study is to evaluate the performance of the five lubricant in the mud with two different formulation (heavy mud and polymer mud). In this experiment, the concentration of 0.5%, 1%, 1.5% of Lubricants is mixed with water-baxsed drilling fluid. To see effect of lubricants, fluids containing lubricant and lubricant-free by Lubricity Tester tests and friction generated between the drilling pipe and the wall measured. Also the influence of lubricants on the rheological properties of the heavy drilling fluid and polymer is investigated using rheology - meter. The results show that among the five lubricant has the best performance for polymer mud RH220, which amounts 31% is reduced torque and for heavy mud, Castor oil has the best performance and torque is reduced by it 15%.