The article suggests a general method for constructing discontinuous interlineation polynomial splines, which, as a partial case, include discontinuous and continuously differentiable splines. The theorems on interlineation and approximation properties of such discontinuous structures are formulated and proved. On the basis of the constructed discontinuous splines, a method for restoration of functions of two variables with first kind discontinuities is created. The theorems on the error of the approximation of discontinuous functions by the constructed discontinuous interlineation splines are proved. Examples are given.
