Experimental investigation of the rotation of dust structures in a DC discharge in a longitudinal strong magnetic field up to B = 1 T has been performed for the first time. The main problem is the occurrence of discharge instability in moderate fields B < 0.1T, which we have been able to solve. The dependence of rotation velocity on B is obtained. In fields B > 0.1T the results are consistent with previous experiments, including rotation inversion. At B < 0.1T (with the exception of the instability region), a much slower increase in the rotation velocity with increasing B is observed than at B > 0.1T. In the region B = 0.3-0.4T, there was a sharp slowing-down of the rotation, apparently due to the instability of the discharge, and a partial degradation of the dust structure occurred.