  We present a new approach for finding conservation laws in the perturbation
theory of black holes which applies for the more general cases of non-Hermitian
equations governing the perturbations. The approach is based on a general
result which establishes that a covariantly conserved current can be obtained
from a solution of any system of homogeneous linear differential equations and
a solution of the adjoint system. It is shown that the results obtained from
the present approach become essentially the same (with some diferences) to
those obtained by means of the traditional methods in the simplest black hole
geometry corresponding to the Schwarzschild space-time. The future applications
of our approach for studying the perturbations of black hole space-time in
string theory is discussed.
