An epidemic of chronic rhinitis in a population of 50 captive spur-thighed tortoises (Testudo graeca graeca) from Palafrugell (Girona, Spain) is described, in which eight animals died and 12 were euthanatized to perform necropsies and post-mortem studies. The main clinical sign was a bilateral, seromucous rhinitis often accompanied by stomatitis and glossitis. Hematology and serum biochemistry were performed in 33 of the 50 ill animals and in 29 healthy tortoises from three disease-free populations. Lymphocyte count, aspartate aminotransferase (AST) activity, and α-globulin levels were significantly higher in the animals from the sick population. The heterophil count was significantly lower in the sick animals. Some of the diseased tortoises also showed a normocytic-normochromic anemia. Lesions were restricted to the respiratory system and oral cavity. Marked epithelial hyperplasia and presence of a severe mixed inflammatory infiltrate in the epithelium of the oral, nasal, and tracheal mucosae were observed. Electron microscopy demonstrated the presence of intracytoplasmic and intranuclear viral particles of the size, shape, and distribution pattern typical of a herpesvirus.