This study was undertaken to observe relationships between patterns of feeding, supplementary-feeding and various maternal, family, and socioeconomic charactereistics in Hae Cheog Apartment area in Cheongdam-dong, Kangnamku, Seoul on July 2 to 12 in 1982. The results were based on a questionnaire from 179 mothers who have the last-born child under two years old. Results were as follows: 1) In socio-demographic characteristics, most of mothers were 25 to 30 years old and 52.0% of index children were under 6 months old. About 56.0% of families were the salaries and 47.0% of them earn over 500,000 won a month. 40.8% of mothers were college graduates and 81.6% of mothers had no occupation. 2) 89.4% of mothers received prenatal care in pregnancy of the index children and mothers who have delivered the child in medical institute were 88.3%. Mothers who recieved education of breast care and feeding technique through prenatal care were 22.4%, 31.8% respectively. 3) In the feeding method, 44.1% of mothers took the breast feeding, 24.0% of them chose the artificial feeding, and 20.7% of them chose the mixed feeding. Mothers who changed the-method from breast feeding to artificial feeding were 10.6% and only 0.6% of mothers changed from artificial feeding to breast feeding. 4) According to the questionnaire, 37 mothers have already finished lactation (no relation with. the beginning of weaning food). In breast feeding, one mother has lactated for $4{\sim}6$ months, one has lactated for $7{\sim}9$ months, four have lactated for $10{\sim}12$ months, and seven have. continued the lactation over 12 months. In artificial and mixed feeding, as the same phenomenon, most of mothers have lactated for more than 12 months. 5) The reasons for feeding method were as follows: In breast feeding, 64.6% of them took the method because they thought the breast milk nutrious, in artificial feeding, 34.9% of them chose it because they had occupation and in the mixed feeding, 67.6% of mothers took the method because of lack of their breast milk. In the case of changing the method from breast feeding to artificial feeding, 42.1% of them answered that they had to change the method because of lack of breast milk. 6) In most of cases, the 4th month was the proper period to begin the weaning food and 32.5% of breast feeding children and 27.6% of artificial feeding children began the weaning food in 4th month. After 4th month, there was no difference between breast feeding and artificial feeding in the beginning of weaning food. 7) In the matter of menstruation, 29.8% of mothers who had breast feeding started their menstruations in 3 months and the rest of them delayed until 12 months. 40% of mothers who had artificial feeding began to menstruate after 2 months and all the rest started within 5 months. 8) The birth interval between the index child and next new child (would-be-born): In breast feeding, the interval of $18{\sim}24$ months had a majority as 50.0%, and in the artificial feeding, the interval of over 24 months marked 66.7% of them. It was analyzed that the birth interval of artificial feeding was wider than that of breast feeding. 9) In the desirable number of children, the mothers who had breast feeding wanted two sons and two daughters as proper children. Those who want two children in disregard of the sex (son or daughter) were 89.3% of breast feeding, and 80.0% of artificial feeding respectively. Mothers who had breast feeding wanted two children rather than one child. 10) In the family planning practice, the rate of practice were 41.9% in breast feeding, and 58.1% in artificial feeding respectively. In the case of breast feeding, the using rate of family planning practice in men was higher than in women.