Diabetes mellitus type 2 is the most common metabolic disorder and it causes an important morbimortality. The structural modifications in the parotid gland (sialosis) had already been described in these patients and could result in variations in the salivary composition, as well as an increase in periodontal and dental pathology. Objectives: to compare the biochemical findings in the saliva and to correlate these biochemical disturbances with the morphologic findings previously described. Patients and methods: clinical information were gathered about 33 patients, 17 had type 2 diabetes. Samples of whole saliva were obtained for biochemical analysis and serum samples to determine metabolic control. Results: in the diabetics saliva we found urea and total proteins increased and reduced levels of microalbumina. Salivary glucose was only augmented in patients with poor metabolic control. Clinical symptoms of xerostomia were present in 76,4% and dental and periodontal disease in 100%. The parotid gland was characterised by the presence of small acini, lipid intracytoplasmic droplets, as well as adipose stroma infiltration. The acinar cytoqueratins? expression was heterogeneous and very positive in the hyperplasic ducts. Conclusions: these biochemical disorders in the saliva of the type 2 diabetic patients would be related with the structural changes previously observed in parotid glands.