Objectives: The current study intended to evaluate the effect of topical application of platelets rich plasma and hyaluronic acid on the healing of experimentally induced tongue ulcer. Materials and methods: 80 white albino rats were used in the study; platelets rich plasma was isolated from 8 rats, by cardiac puncture, then mixed with orabase to form an oral gel. The remaining 72 rats were subjected to tongue ulcer induction. The rats then were divided into: Control group: ulcers were left without any treatment. hyaluronic acid group: ulcers were treated with topical applications of hyaluronic acid gel. platelets rich plasma group: ulcers were treated with topical applications of platelets rich plasma gel. Specimens were taken after 3rd, 7th, and 10th day and processed for histological and immunohistochemical staining for CD31 and KI67. Results: Both platelets rich plasma and hyaluronic acid treated groups showed smaller ulcer size and faster healing histologically and immunohistochemically. The statistical analysis of CD 31 and Ki-67 immunohistochemical reaction along examination period showed significant difference between control group and hyaluronic acid & platelets rich plasma group. Also, there was a significant difference between hyaluronic acid and platelets rich plasma groups at 3rd and 7th day. But, there was non- significant difference between hyaluronic acid & platelets rich plasma groups at 10th day Conclusion: the topical application of platelets rich plasma and hyaluronic acid can accelerate wound healing. PRP showed significant improvement of ulcer healing than HA by stimulating angiogenesis and induction of cellular proliferation.