In the paper a periodic boundary value problem for the Van der Pol differential equation is considered. Since this equation is a nonlinear ordinary differential equation, its solution cannot be found analytically accurately. In this regard, the D.S. Dzhumabaev parameterization method is used to solve the problem. The interval which the problem is considered is divided into two parts, and the values of the desired solution at the beginning points of the subintervals are introduced as additional parameters. The desired function is replaced by the sums of new unknown functions and
additional parameters in the corresponding subintervals, and the original problem is reduced to a boundary value problem for a system of differential equations with parameters. Substituting a solutions of Cauchy problems for ordinary differential equations with parameters into the boundary condition and the continuity condition of the solution at the dividing point a system of nonlinear algebraic equations is constructed. This system is clearly defined only in exceptional cases. Therefore, the values of functions in the system and their derivatives with respect to parameters are found by solving vector and matrix Cauchy problems for differential equations on subintervals. Cauchy problems are solved by the
fourth-order accuracy Runge-Kutta method. The solution to the system of algebraic equations is found by Newton's method. An algorithm for finding an approximate solution to this problem is proposed

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