ВІСНИК Українська медична стоматологічна академія 154 the highest expression was noted in the group, where salivary gland tissue was adjacent to the salivary gland tumour (111, 93±56, 97 versus 8,12±4,4). Correlation analysis of patients with pleomorphic adenoma of the large salivary glands with different fragments of tissues samples demonstrated that the expression level of miRNA-29a differed significantly between the groups (adjacent gland -intact salivary tissue).Conclusions. A sufficiently high level of miRNA-29a expression in the tissues of pleomorphic adenoma in the large salivary glands compared with the normal (intact salivary gland tissue), 10 times as much can be used as a genetic marker for verification (identification) of this type of tumours. Studies of biopsy material from patients with pleomorphic adenoma in the large salivary glands at the genetic level (by expression of miRNAs-29a) confirm the need not only in enucleating of the tumour (partial parotidectomy), but also in performing of subtotal resection with removal of salivary gland adjacent to the tumour.