A fastening clip for a vehicle to mount a vehicle structure to a vehicle body panel is provided. The fastening clip includes a main body that is formed integrally with a support portion disposed between the vehicle structure and the vehicle body panel. An upper end of the main body is inserted into at least one first aperture formed in the vehicle structure and a lower end of the main body is inserted into at least one second aperture formed in the vehicle body panel. The fastening clip further includes a holder which is detachably coupled to the main body and fixes the vehicle structure to the main body, thereby ensuring that the vehicle structure is fastened to or separated from the vehicle body panel more easily.