Introduction: Optimal breast-feeding practices make a major contribution to the promotion of healthy growth and development through much prevention of diarrheal and respiratory diseases which majorly cause morbidity and mortality in under-five children. However, breast-feeding practices remain suboptimality in Ethiopia. Objective: The study objective was to determine the effect of maternal nutrition education on early initiation and exclusive breast-feeding practice in the Hawela Tulla sub-city. Methods: A cluster randomised, parallel-group, single-blinded trial was used. About 310 pregnant women (155 for the intervention group and 155 for the control group) were included. Result: An early initiation of breast-feeding was significantly higher among women who received breast-feeding education than those who did not receive (104(72·7 %) v. 85(59·9 %), P = 0·022) and exclusive breast-feeding practice was also significantly higher among women who received breast-feeding education than those who did not receive (106(74·1 %) v. 86(60·6 %), P = 0·015). Breast-feeding education [AORs 1·55, 95 % CI (1·02, 2·36)], institutional delivery [AOR 2·29, 95 % CI (1·21, 4·35)], vaginal delivery [AOR 2·85, 95 % CI (1·61, 5·41)] and pre-lacteal feeding [AOR 0·47, 95 % CI (0·25, 0·85)] were predictors of early initiation of breast-feeding. Breast-feeding education [AOR 1·72, 95 % CI (1·12, 2·64)] and institutional delivery [AOR 2·36, 95 % CI (1·28, 4·33)] were also determinants of exclusive breast-feeding practices. Conclusion: Breast-feeding education improved early initiation of breast-feeding and exclusive breast-feeding practices. Providing sustained education to women regarding early initiation and exclusive breast-feeding practice should be strengthened.