A cover-material fastening clip includes a locking portion having a guide piece and a hook which includes an extension portion and a distal end portion. The guide piece extends includes a bent portion bent and extended toward the distal end portion. An insertion opening having a predetermined gap and allowing a wire to be inserted therethrough is positioned between the bent portion and the distal end portion. A distal end portion of the guide piece extending from the bent portion is an elastic piece portion being elastically deformed to be spaced from the distal end portion and to widen the insertion opening. In a part of the locking portion, which is located within a range, in which the elastic piece portion can be elastically deformed and thus moved, an escape space is provided to allow a distal end of the elastic piece portion to be positioned therein.