In this paper, the existence of a finite-dimensional solution of a nonlinear integral equation is proved when the right-hand side and the kernel are given approximately. A finite-dimensional regularizing operator is constructed, and it is proved that for n → ∞ and for a special choice of the parameter n from δ, the solution of the finite-dimensional problem converges to the exact solution of the original equation. It is shown by an example that using the Green's function it is possible to approximate a differential operator by an integral operator.