  The purpose of this paper is to investigate some spectral properties of
Sturm-Liouville type problems with interior singularities. Some of the
mathematical aspects necessary for developing own technique presented. By
applying this technique we construct some special solutions of the homogeneous
equation and present a formula and the existence conditions of Green's
function. Further based on this results and introducing operator treatment in
adequate Hilbert space we derive the resolvent operator and prove
selfadjointness of the considered problem.
