Implementing the Baby-Friendly Hospital Initiative (BFHI) programme has been fraught with challenges globally. The study aimed to assess the implementation of the BFHI and breastfeeding practices in healthcare facilities in Ogun State, Nigeria. It was a questionnaire-based cross-sectional study carried out between August and October 2019 among 100 healthcare workers and 110 mothers from health facilities in Ijebu-Ode Local Government Area of Ogun State, Nigeria. Nearly two-thirds (61.0%) of the healthcare workers were community health workers while the others were nurses. Less than a quarter (23.8%) of the healthcare workers had ever attended breastfeeding educational programmes since they started working. About half of the healthcare workers had good knowledge, attitude and practice of BFHI. Nurses had a significantly better practice of BFHI than community health workers. Understaffing was a major limitation to the implementation of BFHI. The mothers had an exclusive breastfeeding rate of 47%. The knowledge, attitude, and practice of BFHI were suboptimal and the exclusive breastfeeding rate among the mothers was low. There is a need to improve staff strength, training and re-training of staff, as well as regular monitoring and evaluation of healthcare facilities on the implementation of BFHI.