The association between proteinuria and congestive cardiac failure was investigated in patients with hypertensive heart disease, cardiomyopathy, rheumatic heart disease and cor pulmonale. In 33 such patients, proteinuria occurred before and after successful treatment of the cardiac failure. Overall there was a wide variation in the degree of proteinuria amongst the various groups and statistical analysis showed that the distribution of levels of proteinuria and the mean levels of proteinuria were statistically different between any two groups of patients, P = 0.05. Biopsy proven hypertensive nephrosclerosis was found to be a cause of heavy proteinuria which was in the nephrotic range in two such patients. Congestive cardiac failure due to hypertensive heart disease should be included in the differential diagnosis of massive proteinuria even in the absence of renal insufficiency.