The atomic force microscope was used to research experimentally the boundary slip of the silicon substrate and pure squalane on solidliquid interface in micronano gap.By taking the effect of doublelayer electronic force between the solidliquid interfaces into account,the surface charge densities of sphere of silicon dioxide and solid surface specimen were analyzed,and a measurement of hydrodynamic force of squalane was made.Results indicate that at the conditions of without considering the gravity and inertia force of the small ball and intermolecular force,the ball is mainly exerted doublelayer force and hydrodynamic force during the process when the sphere approaches the solid specimen vertically.At low speeds,the doublelayer force is dominant.In squalane liquid environment,in the process of a probe approaching the silicon substrate,the doublelayer force is showed the gravitational force,and its size is independent of the approaching velocity,In the range of approaching velocity of experiment,the boundary slip occurs on the interface of the surface of Si(100) and squalane,and the degree of slip is increased with the increasing of the velocity.