  We review some results of applying the higher covariant derivative
regularization to the investigation of quantum corrections structure in N=1
supersymmetric theories. In particular, we demonstrate that all integrals,
defining the Gell-Mann--Low function in supersymmetric theories, are integrals
of total derivatives. As a consequence, there is an identity for Green
functions, which does not follow from any known symmetry of the theory, in N=1
supersymmetric theories. We also discuss how to derive the exact
$\beta$-function by methods of the perturbation theory.
