Equine sialolithiasis is an uncommon, painful condition in horses, where a calcified mass or sialolith forms within the horse's salivary gland, usually the parotid duct. The presence of the sialolith causes obstruction of the horse's salivary duct, salivary gland dysfunction, oral mucosal ulceration. Equine sialolithiasis can also cause digestive disorders in affected horses, for saliva plays a significant role in preventing oesophageal obstruction, its high bicarbonate content, and gastric buffering function.

Sialoliths are usually quite obvious, and easily recognized upon palpation of the enlargements on the horse's face, often occurring bilaterally.