Based on thevirtual workincrement equation for thethree-dimensional continuum,in-terpolating the translations and rotations respectively,the Updated Lagrangian forrnulationfor large displacements and rotations analysis of beam structures is developed .Consideredthe effect of axial.shearing and flexural deformations,a new type of geometric stiffness ma-trix is presented.Numerical solution showed that the program developed by the proposedmethod in this paper is available for the analysis of strong non-linear behavior of structures.Under the assumption of rotational increment in every step is small,problem of arbitrarilylarge rotions is able to be solved.