Objective: Therapeutic properties of Sanguisorba L. genus plants are supported by numerous in vivo and in vitro studies showing the anti-viral, anti-ulcerogenic, anti-cancer, anti-acetylcholinesterase, radioprotective, anti-allergic, and anti-inflammatory activities. The present study was designed to investigate anti-arthritic activity of the “Sanguisorba minor subsp. balearica (Bourg. ex Nyman) Muñoz Garm. & C.Navarro” (Smb), a subspecies of Sanguisorba L. genus, on Complete Freund’s Adjuvant induced (CFA-induced) arthritic rat model. Material and Method: The extract of aerial parts of the Smb was obtained by the consecutive steps of maceration process. The phytochemical content of the extract was analyzed by the High-Performance Liquid Chromatography (HPLC) method. Complete Freund’s Adjuvant-induced arthritic rats were used to examine the anti-arthritic activity of the plant extract. Result and Discussion: HPLC analysis revealed a high amount of phenolic compounds in the Smb extract. The identified phenolics are ellagic acid, gallic acid, quercetin dehydrate and p-coumaric acid with the concentrations of 4.1288; 2.6342; 0.0871 and 0.0633 ppm, respectively. Injection of Smb extract caused a decrease in paw thickness in the CFA-induced arthritic animals. The decrease in paw thicknesses of animals treated by quercetin and Smb 70 mg/kg groups was higher than diclofenac sodium group. Smb 34 mg/kg group also showed a decrease in paw thickness, but it was lower compared to quercetin and Smb 70 mg/kg groups and higher than the diclofenac sodium group. According to the histopathological evaluations of the joint tissues, both 34 mg/kg and 70 mg/kg Smb extract treatment were improved the inflammatory deformations related to arthritis on the rats.