ObjectiveTo preliminarily predict the targets and signaling pathways of indole-3-methanol in the treatment of obesity based on molecular docking technology and network pharmacology， and then verify the prediction results by the experiment in vitro. MethodThe pharmacological targets of indole-3-methanol were obtained from SwissTargetPrediction and literature review. Obesity-related targets were obtained from Online Mendelian Inheritance in Man （OMIM）， GeneCards， and Comparative Toxicogenomics Database （CTD）. The protein-protein interaction network of the targets of indole-3-methanol and obesity was built by STRING. Cytoscape 3.8.2 was used for target screening. Gene ontology （GO） functional annotation and Kyoto Encyclopedia of Genes and Genomes （KEGG） pathway enrichment were performed for the common targets shared by obesity and indole-3-methanol in DAVID 6.8. AutoDock Vina 1.1.2 was employed to perform the molecular docking between indole-3-methanol and disease targets. Finally， the in vitro experiment was carried out to verify the anti-obesity effect of indole-3-methanol. ResultIndole-3-methanol and obesity shared 80 common targets， which included matrix metalloproteinase （MMP）-9， Janus kinase （JAK） 2， etc. KEGG enrichment predicted that indole-3-methanol mainly acted on tumor necrosis factor （TNF）， vascular endothelial growth factor （VEGF）， tyrosine kinase receptor 2 （ErbB2）， and epidermal growth factor receptor （EGFR） signaling pathways in the treatment of obesity. Molecular docking showed that indole-3-methanol had good binding activity with fat mass and obesity-associated protein （FTO）. The results of Western blot， MTT assay， and oil-red O staining showed that indole-3-methanol down-regulated the expression of FTO in 3T3-L1 cells （P<0.05）. ConclusionIndole-3-methanol may treat obesity by down-regulating the expression of FTO protein and further inhibiting adipocyte proliferation. This study provides an experimental basis for deciphering the anti-obesity mechanism of indole-3-methanol.