Numerical methods and studies of differential properties of an R ν -weak solution are presented for boundary value problems with a divergent Dirichlet integral of the solution.In this paper we discuss numerical methods and studies of differential properties of boundary value problems for elliptic equations possessing strong singularity. A boundary value problem is said to possess strong singularity if its solution u(x) does not belong to the Sobolev space W 1 2 H 1 or, in other words, the Dirichlet integral of the solution u(x) diverges.There exists a complete theory of classic solutions to boundary value problems with smooth initial data (coefficients of equations, right-hand sides of equations, boundary conditions) and a sufficiently smooth domain boundary (see, e.g., [1,11,13,17]). A grid method for boundary value problems with singularity of the solution caused by the angles of the domain boundary was first considered by Volkov [48].Based on the notion of a weak solution, extensive studies of boundary value problems with discontinuous initial data and nonsmooth domain boundaries were performed for Sobolev and various weighted spaces (see, e.g., [10,12,15,16,18]). Based on the Galerkin approach, theories of difference schemes, finite volumes, and finite element methods were elaborated for determination of approximate weak solutions (see, e.g., [8,45,46] and others).Boundary value problems with strong singularity caused by the singularity in the initial data or by the internal properties of the solution are found in the physics of plasma and gas discharge, electrodynamics, nuclear physics, nonlinear optics, and other branches of physics. In particular cases, numerical methods for problems of electrodynamics and quantum mechanics with strong singularity, were constructed based on separation of singular and regular components, mesh refinement near singular points, multiplicative extraction of singularities, etc. (see, e.g., [2,3,9,47]).In [21] it was proposed to define the solution to a boundary value problem with strong singularity as an R ν -weak solution in a weighted Sobolev space. This new notion of the solution allows one to discriminate two classes of boundary value *