This study was conducted to evaluate the knowledge, attitude and educational needs regarding breast feeding of women’smothers and mother-in-laws with a grandchild aged less than 24 months. The degree of knowledge regarding breast feedingwas 14.84 points out of 25 points, while the attitude toward breast feeding was 83.88 points. Additionally, 16.4% of therespondents reported that education regarding breast feeding was unnecessary. There were significant differences inknowledge regarding breast feeding among individuals of different age (p<0.05), economic status (p<0.05), and withdifferent aged grandchildren (p<0.05). Additionally, there were significant differences in attitude toward breast feedingbased on the type of feeding (p<0.05), the practice of breast feeding (p<0.01), and reasons for low breast feeding rate(p<0.05). There was a significant positive correlation between knowledge regarding breast feeding and attitude towardbreast feeding. The factors affecting knowledge regarding breast feeding were attitude toward breast feeding and middleclasseconomic status. In addition, the factors affecting attitude toward breast feeding included knowledge of breast feedingand the practice of breast feeding. Overall, the subjects had high educational needs regarding breast feeding; therefore,women’s mothers and mother-in-laws should be given the opportunity for various types of education to improve their breastfeeding knowledge.