Rotational-type mesodefects — strain induced junction disclinations, are formed at joints and ledges of high-angle grain boundaries during plastic deformation of polycrystals. The strength of these mesodefects increases with deformation and, as a result, they create non-uniform elastic stress fields, which significantly affect the processes of structure formation, strain hardening and material’s fracture. In the present work, the interaction of a slip band propagating in a grain body under the action of an external stress field with an elastic field of wedge disclination is investigated by the discrete dislocation dynamics simulation method. The simulation results show that the behavior of the front of the band has common regularities. For a given distance between the slip band and the disclination y0, the behavior of the dislocation cluster in the front of the band essentially depends on the distance between the slip planes of the dislocations h. For small h, it is similar to the behavior of a dislocation pile-up. However, the maximum density of dislocations occurs not in the head of the cluster, as in the classical blocked dislocation pile-up, but in its central part. An increase in the distance h between dislocations slip planes leads to a “splitting” of the front of the band. For larger h the front of the band transforms into a broken from both sides dislocation wall. The minimal distance hc, above which such dislocation wall is formed, depends on the disclination strength ω0 and the distance y0. The maximal misorientation of the wall is equal to the disclination strength ω0 at y0 = 0. With an increase in the external stress, the wall overcomes the force barrier of the disclination and moves as a whole to the lateral surface of the crystal. Multiple reiteration of this process leads to the possible appearance of the system of broken from both sides dislocation walls in the body of grain.