A cardiovascular comorbidity (CVC) in psychiatric patients represents a simultaneous occurrence of a cardiovascular and a mental illness in the same patient regardless of the order of occurrence or of the cause and effect relationship that conjoins them. The objective was to determine the frequency and sort of the CVC in previously hospitalized patients with diagnoses of schizophrenic and affective disorders along with the differences in distribution of said disorders between the two groups of patients. Design-wise this is a retrospective study of intersections. It is based on the analytics of medical data (the history of disease along with the internal medicine consultant reviews) of the hospitalized patients in the Clinic for psychiatric disorders “Dr. Laza Lazarević” in Belgrade during the period between November 2014 and February 2015. Patients who were involved were older than 18 and they had diagnoses of schizophrenic disorders (F20-F29) and affective disorders (F30-F39), according to diagnostic criteria in the International classification of diseases 10 (ICD-10). CVC which were previously diagnosed or registered during the examination we separated into the following groups according to ICD-10: hypertension (HTA) I10, cardiac arrhythmia (CA) I47-I49, chronic cardiomyopathy (CMP) I42-I43 and ischemic heart disease (IHD) 120-125. The two groups of patients were analyzed according with socio-demographic characteristics (gender and age range) and CVC diagnosed according to MKB-10 classification. CVC were registered in 66% of the patients diagnosed with schizophrenia and 34% of the patients with affective disorders. Hypertension was most common in both groups of patients following with cardiac arrhythmia. Cardiac arrhythmias were statistically significantly more common in patients diagnosed with schizophrenic disorders (p<0.001) compared to patients with affective disorders. The frequency of hypertension, ischemic heart disease and chronic cardiomyopathy rises with age in both groups of patients. The results of this research confirm a high degree of CVC in hospitalized patients with diagnoses of schizophrenic and affective disorders (especially cardiac arrhythmia and hypertension). A multidisciplinary team is the key for diagnosing and monitoring patients with schizophrenic and affective diseases in both primary and secondary preventions.