Abstarct: In this study, a method has been introduced as a new approach to study the static and dynamic behavior of electrostatically actuated nanobeams which can be used as biosensors. baxsed on the nonlocal differential constitutive relation of Eringen, the nonlocal equations of motion are derived from Hamilton’s principle. The model includes one dimensional Reynolds equation with slip condition in boundaries to takes into account the squeeze film damping of the fluid between the nanobeam and the electrode. In analyzing the behavior of the nanobeam, the Galerkin method was used to discretize two coupled partial-differential equations, namely the nonlocal beam deflection equation and the Reynolds squeeze film damping equation. The static deflection of the nanobeam and its linear natural frequencies is investigated under the DC component of electrostatic actuation. The frequency response of AC component of electrostatic actuation with and without accounting the squeeze film damping is derived using multiple scale method. The results show that squeeze film damping decreases the amplitude of vibration and closes the jump frequency and the linear natural frequency together. Also the results indicate that for the first mode the effective nonlinearity is of the hardening type, whereas for the third mode the effective nonlinearity can switches to the softening type by increasing DC component of electrostatic actuation.