Oral mucosal cancer is diagnosed worldwide. There are approximately 350,000 patients annually and it accounts for 5% of all malignant neoplasms detected in Europe and the USA. More than 60% of patients with initial treatment in medical institutions are assigned III–IV stage, which requires combined or complex treatment. Under the influence of chemo-radiation therapy, the salivary glands are affected and the physico-chemical properties of saliva change: viscosity, pH, salivation rate, etc. The study involved 89 people from the V.M. Efetov Crimean Republican Oncological Clinical Dispensary with a diagnosis of cancer of the oral mucosa, who, depending on the type of treatment (developed or traditional), were divided into two groups: the main one – using Laetrile in the form of rinses or oral baths for 8–14 days and the control – antitumor treatment according to the protocol (0.06% chlorhexidine solution, ointments for the elements of the lesion – levomycol, vaseline, pharmacy lotion and decoctions of chamomile and sage herbs). A clinical and laboratory evaluation of the salivation function was performed: the volume, salivation rate and relative viscosity of the oral fluid were studied. Oral fluid after irritation of the tongue with a food irritant (0.5% citric acid) was collected in a graduated tube for 5–10 minutes and the volume was determined. The salivation rate and saliva viscosity were determined using an Oswald’s viscometer using the technique of T.L. Redinova (1986). The features of salivation dysfunction in oncopatients receiving chemo-radiation therapy of the oral cavity are a decrease in volume (0.14 ± 0.01 ml) and velocity (0.42 ± 0.018 ml/min), as well as an increase in viscosity (7.42 ± 0.25 p.u.) saliva. The use of Laetrile for 10–14 days from the beginning of the course of chemo-radiation therapy can significantly prevent a decrease in the volume and increase in the viscosity of saliva and minimize the associated decrease in quality of life.