Integrated management of childhood illness (IMCI) is an integrated approach to child Health that focuses on the wellbeing of the whole child (WHO, 2018). Infants and child mortality remains high in developing countries where almost 10 million deaths occur annually in children under five years old (UNICEF, 2016). The study is on the knowledge and implementation of integrated management of childhood illness among health workers in Model Primary Health care Centre Rumuodomaya, Rivers State. The objectives of the study are to assess the level of knowledge of IMCI, to investigate the extent of implementation of IMCI. To find out the barriers to the implementation of IMCI. The target population of the study was 30 health care workers in Primary Health Centre and the sample size of all the 30 health workers was used for the study because the population size was few. A purposive sampling technique was used. The instrument used for data collection was a selfconstructed questionnaire. Data was analyzed using percentage, table and mean scores which revealed there is high level of knowledge of integrated management of childhood illness among health care workers. With grand mean of 4.15± 0.76, Investigate the extent to which Integrated Management of Childhood Illness (IMCI) is implemented among health care workers with the grand mean of 4.04± 0.59. There are barriers to the implementation of integrated management of childhood illness (IMCI) among health workers. Some of these barriers are misunderstanding about how to administer oral treatment antibiotic (3.83 ± 0.46), unavailability of essential drugs (4.07 ± 0.78), malnutrition and uneducated caregiver (4.07 ± 0.25). With respect to the finding, implications to nursing were stated and recommendations were made, suggestion for further studies were also made