This descriptive study was cone to investigate the incidence of and reasons for the interruption of breast-feeding by married nurses. For this purpose, data was collected from married nurses, each of whose last child was under five years old, living in Seoul, Tong Hae, Sam Chok and Kang Rung. The number of children involved was 208. The data was collected from various places in Seoul, Tong Hae, Sam Chok and Kang Rung area, using 150 survey questionnaires. The results of the study were as follows: 1. The proportion of children receiving breast-feeding was 1.4%, mixed feeding 33.8% and milk feeding 64.9%. The most frequent duration of breast-feeding was one month (80.2%). 2. The major reasons for breast-feeding were the health of the child 97%, and for emotional attachment with the child 75%. 3. The major reasons for interrupting breast-feeding were the job of mother 79.5%, and an abnormality of the breast or nipple 26.0%. 4. The major reasons for quitting breast-feeding were the job of mother 89.2%, insufficient breast milk 34.2%, and breast pain 19.9%. The above results suggest that the breast-feeding ratio in married nurses is very low. Therefore it is recommended that education about and propagation of breast-feeding be carried out. To enhance and promote breast-feeding, hospital managers should provide a comfortable environment, which is conducive to breast-feeding.