Feline gingivostomatitis is an inflammatory syndrome of the oral mucosa characterized by chronic pain. Its multifactorial etiology and debilitating consequences are associated with difficult clinical management and high relapse rates even after invasive interventions, potentially severely compromising the animals’ quality of life. Cannabidiol (CBD) has been investigated for its anti-inflammatory, antioxidant, analgesic, and immunomodulatory effects and is considered a potential therapeutic alternative for chronic inflammatory diseases. The present report aims to describe a significant clinical improvement in a 5-year-old mixed-breed male cat affected by feline gingivostomatitis, presenting with hyporexia and sialorrhea. A broad-spectrum Cannabis oil rich in CBD was prescribed at doses ranging from 0.5 to 1.0 mg/kg, administered twice daily for two months. Early clinical improvement was observed from the first day of administration, with a dose-dependent response, ultimately resulting in an overall satisfactory clinical outcome. Therefore, it can be concluded that the clinical application of a broad-spectrum Cannabis oil rich in CBD may represent a promising therapeutic alternative for cats affected by feline gingivostomatitis, especially in refractory cases or those with limitations to conventional therapies.