This study was designed based on the hypothesis that synovial fluid (SF) can reduce scar formation in incisional skin wounds, because of rich hyaluronic acid (HA) contents and viscoelastic properties. For this purpose, the efficacy of intralesional injection of SF in a primary closure model of incisional skin wound was investigated. A total of 36 male mice, 8–12 weeks old and weighing 39–44g, were randomly divided into two equal groups, i.e., an untreated control group (Group-C) and an SF group (Group-S). A 3-cm long skin incision involving all the layers was made at the back of each mouse.  The skin wound was closed with a simple interrupted suturing technique. In Group-S only, SF was injected into the wound area before its closure. Six animals in each group were sacrificed at 7, 14, and 21 days of incision and underwent macroscopic and histopathological examination. For the histological examination, tissue sections were stained with Crossmann’s modified triple staining technique. Results showed that wound healing was faster in the SF group than in the control group. This difference was more evident at 14 days after the incision. In addition, the significant decrease in both the number of inflammatory cells and granulation tissue at 14 days after the incision in the SF group than the control indicated that SF accelerated the healing phase. In conclusion, the present study reveals that the use of SF as a source of HA accelerates wound healing and is effective in preventing fibrosis in incisional skin wounds.