Cardiac mensuration by the reentgenological heart volume method was varried out on 225 Korean infants, 111 cases of whom were male, 14 were female. RESULTS : 1. Predicted heart volume at one month of age is 26.44$pm$2.99㎤ in male, 38.93$pm$2.96㎤ in female and at eleven month of age 99.37$pm$3.96㎤ in male, 100.40$pm$2.46㎤ in female. 2. Relative heart volume at one month of age is 135.84$pm$17.92㎤/$m^2$ in male, 140.00$pm$15.29㎤ /$m^2$ and at age of eleven moth 240.05$pm$15.98㎥/$m^2$ in male, 236.82$pm$6.25㎤/$m^2$ in female. 3. In comparision with American standard value by Mannheimer, Korean infants show smaller heart volume generally.