Objective: In order to obtain proteins related with the occurrence and development of silicosis and further reveal the development mechanism of silicosis, we collected alveolar macrophages from lung lavage fluid of silicosis patients, and studied the different proteins in alveolar macrophages of silicosis patients at different stages. Methods: A total of 31 patients with silicosis were selected who were male and who were exposed to dust, or dust removal within 2 years prior to our study. Two-dimensional gel electrophoresis was used to isolate the differential proteins. Image Master 2D Platinum software was used to identify differential protein spots. This method was used to identify differential spots, namely New ultrafleXtreme reflective tandem matrix assisted laser desorption time of flight mass spectrometry. GO, KEGG Pathway and PPI analysis of differential proteins were carried out by bioinformatics. Results: Through bioinformatics analysis, we found that these differential proteins mainly participate in the pathway of fatty acid degradation, valine, leucine and isoleucine degradation, lysine degradation, tryptophan metabolism, pyruvate metabolism, metabolic pathways, etc. Bioinformatics analysis showed that there were interactions between ECHS1 and ALDH2. Conclusions: Using differential proteomics, we found that the proteins associated with silicosis development in alveolar macrophages were ANXA4, PRDX4, ERP29, KRT10, FTL, ECHS1, and ALDH2; the findings of which enriched the alveolar macrophage protein library of silicosis. Through bioinformatics analysis, the main mechanisms of pulmonary alveolar macrophages involved in the development of silicosis were fatty acid metabolism, MAPK activity regulation, oxidative stress, notch signaling pathway, and negative regulation of interleukin-8 secretion. The expression of ECHS1 protein in the pulmonary dust deposition group was different from the silicosis groups of grade one and two. ECHS1 may be the key protein in the development of silicosis.