Introduction: To address health problem of the rural community, Ethiopia launched Health Extension Program in 2003. Mother and child have been facing different problems and due to poor access to modern health care facilities. Lack of effective demands to utilize the available service also has its own contribution to the problems. Objective: The aim of this study was to assess the status of Health Extension Service Utilization and Associated Factors among Community of Merti Woreda Arsi Zone, Oromia Regional State, Ethiopia. Methodology: Community based, quantitative cross-sectional study using structured questionnaires were carried out. A total of 604 households were selected from each kebeles through systematic sampling from random starting point from household registration book using a number between one and sampling interval. The data was entered to Epi Info version 7computer software and transferred to SPSS version 21 computer software programs. Descriptive statistics was done for each variables, bivariate analysis between dependent and independent variables was performed. Multivariate analysis was done to control for possible confounding variable finally P-Value < 0.05 with CI was used as level of significance. Results: The level of community utilization of health extension service was 92.4%. Even though the health extension service is high, the implementation is found to be low in some packages such as women’s immunization service, delivery, postnatal care service, community conversation, and model family. Age, educational status, religion, language, and knowledge about health extension service were identified as the independent factors affecting community health extension services utilization. Further studies should be undertaken to determine the level and factors affecting utilization of health extension service from the perspective of health extension workers on a wider scale. Conclusion: The level of community utilization of health extension service has registered relatively higher results as compared to the previous studies. Age, educational status, religion, language, and knowledge about health extension service were identified as the independent factors affecting community health extension services utilization.