104 Background: Successful cancer treatment depends on many factors, not merely only medical aspects, but also other things, such as patients’ ability to comply the treatment schedule, patients’ understanding of the treatment steps and process, to avoid delay in administrative process, etc. These non-medical aspects are significantly affects patients ability to complete the treatment, especially in developing country including Indonesia. This study aims to empower a group of patient navigator (PN) in a Radiation Oncology Unit in one of the biggest national top referral hospital in Indonesia, Cipto Mangunkusumo Hospital. Methods: For the preparation of the project, 14 lay patient navigators and 1 physical navigator who were all cancer survivors nor volunteer from the Cancer Information and Support Center (CISC) Group, were trained for basic patient navigation training and basic cancer knowledge, as well as communication skills training. The navigators also trained for emergency response (basic life support, hospital emergency codes and responses, etc). This program is under supervision of the American Cancer Society (ACS). As for the flow of the process, all new cancer patients in the Department will be introduced to PN for screening of their non-medical aspects potential barriers using a self-made questionnaire. Fourteen risk potential problems are listed in the questionnaires, including accommodation, transportation, financial, psycho-social and family/support system problems. Results: The program was launched in September 2022 in the Department of Radiation Oncology Cipto Mangunkusumo Hospital. Patients with all cancer types are included in the program. Until Feb 2023, more than 500 patients have been screened for their potential barriers in going through the treatment. Most of the significant helps given by the PN were allocating a free accommodation for the patients living far from the hospital, free transportation pick up to the hospital, home visits for those who drop outs from treatment and give the supports needed to come back to therapy, and psychosocial-emotional supports. Conclusions: Patient navigation program in our Department was found to be effective in helping our cancer patients completing their treatment.