Radioiodine therapy currently finds wide application for the treatment of malignant diseases of the thyroid gland and is a mandatory diagnostic and therapeutic procedure which significantly improves the prognosis of the clinical course of the underlying diseases and the patient’s life. However, the radioiodine therapy is known to be frequently associated with the damage to the salivary glands. At the same time, the problem of variability, intensity, dose dependence as well as the reversibility of the radioiodine damage remains poorly explored. The objective of the present publication is to review the current literature concerning salivary gland lesions associated with radioiodine therapy and to report the clinical observation of a patient who underwent total strumectomy and passed through one course of radioiodine therapy. Material and methods. The clinical and laboratory examination of the patient’s salivary glands has been performed with the use of general, individual and special methods, such as sialometry. ultrasound study, puncture, and scintigraphy with the use of 99mTc-pertechnetate. Results. The peculiar features of the case in question include, firstly, the absence of complaints of dryness in the mouth despite practically complete dysfunction of the parotid salivary glands and the impaired function of the right submandibular salivary gland within 1.5 years after the radioiodine treatment and compensation of hypothyroidism; secondly, the unilateral enlargement of the right submandibular salivary gland half a year after the radioiodine therapy revealed by the scintigraphic study. After a year, the gland spontaneously decreased in size, became undetectable visually, and swelled during meals, but remained slightly enlarged on palpation, being of soft and elastic consistency.