The invention provides a manufacturing method of a head rest support with high strength and light weight. The manufacturing method is characterized by comprising the following steps: (a) cutting off materials for the rod-shaped or pipe-shaped head rest support, and then processing a clamping groove and two front ends; (b) performing the oxynitrocarburizing procedure on the materials processed in the step (a); (c) performing surface machining on the materials processed in the step (b); and (d) bending the materials processed in the step (c). Therefore, the head rest support which has the advantages of high strength, light weight, good corrosion resistance, diversified color phases and attractive appearance can be obtained.