The purpose of this study is to investigate the effectiveness of Ficus deltoidea (F. deltoidea) as an anti-oral ulcer on animal models. Adult male Sprague Dawley rats were sedated with Nembutal through intraperitoneal route; oral ulcer models were made by applying 99.5% of glacial acetic acid moistened paper disc on rat buccal mucosa. Four groups of these rats were treated respectively with: no treatment (group 1: negative control); Triamcinolone acetonide (group 2: positive control); 250 mg kg^-1 F. deltoidea extract (group 3: experimental); 500 mg kg^-1 F. deltoidea extract (group 4: experimental) for 10 consecutive days, respectively. On days 2, 4, 6, 8 and 10, the ulcers size was assessed. Data was analysed statistically by using SPSS. The negative control rats exhibited buccal mucosa injury whereas treatment with F. deltoidea and Triamcinolone acetonide resulted in significantly reduced size of oral ulcer. The percentage of inhibitory area of oral ulcer was more prominent in 500 mg kg^-1 F. deltoidea extract than 250 mg kg^-1. Meanwhile, in vivo study showed that F. deltoidea extract not toxic up to 1000 mg kg^-1. The present findings suggest that F. deltoidea extract effectively accelerates oral ulcer healing process, and could therefore be developed as a therapeutic agent for healing oral ulcer.