Lectures are given on the method of numerical simulation of nonlinear dynamic behavior of solid. Specifically, a problem of static equilibrium of a nonlinear elastic body is discussed. Explanations are made about the theory of the nonlinear finite element method, method of discretization, actual programming and a system for solving a nonlinear algebraic equation. First, a review is made of mathematical models in solid mechanical problems, and nonlinear behavior is organized and classified to capture a perspective. Then, a problem of static equilibrium of a nonlinear elastic body is formulated. The procedure for deriving a finite element disretization equation from the weak form of the equilibrium equation is explained. Then, the constitutive rule and equilibrium equation are discretized separately, and explanations are made about the essence of the nonlinear finite element method and the basics concerning the performance of elements. Next, explanations are made about the solution of a nonlinear algebraic equation obtained by discretization. The focus of explanation is placed on the secant method, Newton's method and incremental method. Lectures are given mainly on the formulation and algorithm in finite element method and implementation in analysis codes. Linear and nonlinear finite element programs usable in MATLAB and OCTAVE are distributed and explained. Drills are implemented for modifying the programs.