96-25E

The exact results for thermodynamical properties of one-dimensional spin-$1/2$ isotropic $XY$ model with Dzyaloshinskii-Moriya interaction in random lorentzian transverse field are obtained. This permits to discuss some approximate methods of disordered spin systems theory. The approximate scheme of examining the thermodynamics of one-dimensional spin-$1/2$ $XXZ$ Heisenberg model with Dzyaloshinskii-Moriya interaction in random lorentzian field is suggested.