The worsening of soil salinization has become an important factor limiting crop yield and quality. Pyropia haitanensis grows in the intertidal zone, and has extremely high salt tolerance. The response mechanism of organisms exposed to stress is linked to energy metabolism and protein processing. The worsening of soil salinization has become an important factor limiting crop yield and quality. Pyropia haitanensis grows in the intertidal zone, and has extremely high salt tolerance. The response mechanism of organisms exposed to stress is linked to energy metabolism and protein processing. Therefore, the aim of this study was to analyze the response mechanism of Pyropia haitanensis to high and low salt stress using dia technique.