Abstract: Based on the Coulomb’s concept that the earth pressure against the back of a retaining wall is a thrust exerted by the sliding soil wedge formed by the back of the wall and a plane passing through the bottom edge of the wall with an the angle of inclination θ.The differential equation of first order is set up by the equilibrium of forces on the slice taken out from the wedge. The theoretical answers to the unit earth pressures, the resultant earth pressures and the points of application of the resultant earth pressures on retaining wall are obtained for the wall movement mode of rotation about base. The comparisons are made among the formula presented here, the formula for the wall movement mode of translation, the Coulomb’s formula and some experimental observations. It is demonstrated that the magnitudes of the resultant earth pressures for the wall movement mode of rotation about base is equal to that determined by the formula for the wall movement mode of translation and the Coulomb’s theory, but the distribution of the earth pressure and the points of application of the resultant earth pressures are significantly different.