Objective. There are two points of view on the relation between anxiety and depression: they are comorbid diseases or they are symptoms of the same disease. This inconsistency complicates the diagnosis of anxiety and depressive disorders in clinical practice, in particular in elderly patients. We attempted to study the nosological structure of anxiety states in elderly patients and work out recommendations on differential diagnosis of anxiety disorders and depressions. Material and methods. A main group included 80 elderly patients with anxiety disorders, 80 patients with anxious depression were enrolled in comparison group. These groups were selected on the basis of the primary diagnosis made before enrollment patients into the study. Results. After the detailed examination of patients with anxiety disorders, the diagnosis has been changed in 67.5% of patients. Symptoms of all patients with hypochondriac, somatisized and somatoform pain disorders were corresponded to atypical anxious depression. Duration and severity of psychogenic disorders of adaptation and acute reactions to stress were also corresponded to the diagnosis of depression. All patients with obsessive-compulsive disorders had typical symptoms of neurosis-like schizophrenia, these patients were excluded from the study. After the revision of diagnoses, the group with anxiety disorders comprised 26 patients and the group with depression increased up to 131 patients. A between-group comparison of clinical/anamnesis data showed that mean age of patients with depression (59.7 years) was significantly higher than that of patients with anxiety disorders (56 years). Levels of anxiety measured with the Hamilton scale (HAM-A) were similar in both groups. MADRS scores were significantly higher in the depression group (27.9) compared to patients with anxiety disorders (16.5). Conclusion. The most frequent diagnoses that mask depression in elderly people are hypochondriac, somatisized and somatoform pain disorders as well as acute reactions to stress and disorders of adaptation. Somatoform autonomic dysfunction and agoraphobia are less frequent diagnoses. Clinical-psychopathological examination of elderly patients with these disorders requires a careful search for symptoms of a possible atypical depression. Definite diagnosis is necessary for adequate treatment.