Abstract: In order to guarantee the efficiency of sweeping method to generate hexahedral meshes, the swept surface of swept volume has to be meshed with structured meshes, but affected by the sub-domain produced by geometries connecting to the swept surface, there are some local unstructured meshes in the meshes of swept surface, which hinders the application of sweeping method.To solve this problem, a new sweeping method is proposed, the meshes of the surfaces of swept volume with sub-domain constraints are divided as structured meshes and unstructured meshes, structured meshes are grouped with the unstructured meshes in other surface to form a new sweeping group, the missing boundary nodes are supplemented in every sweeping group, then the internal nodes are generated using interpolation to finish the whole nodes of hexahedral meshes.This method extends the application of sweeping method.Examples demonstrate that the proposed method is reliable and robust, and that can handle the hexahedral mesh generation problem of complex two-and-one-half dimensional geometries.