Evaluation of the quality of cylindrical optical elements has always presented severe difficulties. Previous techniques have depended on either indirect methods or methods providing relatively poor resolution. A new basic interferometric technique makes possible direct figure characterization for cylindrical optics utilizing conventional interferometric equipment. Several variations are possible for different test conditions for both cylindrical mirrors and cylindrical lenses. This measurement technique has been applied successfully to cylindrical mirrors and lenses. The basic technique and several variations are presented and discussed. Examples of the results of actual tests are included with test conditions specified, and a complete listing of necessary conventional interferometric equipment is given.