A method of manufacturing a suspension structure including providing a substrate, forming a first photoresist pattern on the substrate, heating the first photoresist pattern to harden it as a sacrificial layer, forming a second photoresist pattern on the substrate and the sacrificial layer, the second photoresist pattern exposing a part of the substrate and the sacrificial layer, forming a structure layer on the substrate, the second photoresist pattern, and the sacrificial layer, performing a lift off process to remove the second photoresist pattern and the structure layer above the second photoresist pattern, and performing a dry etching process to remove the sacrificial layer in order to make the structure layer become the suspension structure.