Hirudo nipponia is an important traditional Chinese medicine resource in China, and the secretions of its salivary glands contain a variety of protein bioactive substances, but due to the low concentration and abundance, they have not been more characterized, and the exploration of its salivary glands is of great significance for the study of the medicinal value and secretion mechanism of leeches. Methods: The expression of differential proteins in salivary gland tissues under starvation (D30) and feeding (D0) states was compared by label-free protein quantification and bioinformatics analysis.