The effects of cobalt contents on the substructures and textures of Ni-Co alloys deformed by rolling have been studied. The substructures of Ni-Co alloys rolled 50% and 93% show a strong tendency to form cells with decreasing cobalt content, and the cell size becomes smaller with increasing deformation degree for the same alloys. The rolling textures of all the Ni-Co alloys rolled 93% are mainly composed of (220) plane parallel to the rolling direction, independent of the level of cobalt content.