The number of older adults in Indonesia continues to increase each year due to rising life expectancy alongside improvements in the quality of health services. The types of diseases commonly experienced by older adults are chronic conditions such as diabetes mellitus, hypertension, and heart disease, all of which require continuous and routine treatment. Medication adherence among the elderly remains a serious concern. This study, conducted within the Prolanis program at Bululawang Community Health Center, aimed to determine and analyze the relationship between the level of knowledge of older adults and their adherence to taking prescribed medications. The study population consisted of all older adults enrolled in the Prolanis program at Bululawang Community Health Center, totaling 197 individuals. A purposive sampling technique was used to obtain a sample of 74 respondents. Knowledge was measured using a questionnaire developed by Herawati & Setiawan consisting of ten closed-ended questions. The validity of the knowledge questionnaire was tested using item-total correlation, and all items were declared valid. The reliability test showed good internal consistency with a Cronbach’s alpha coefficient greater than 0.70. Meanwhile, medication adherence was assessed using the short version of the Morisky Medication Adherence Scale (MMAS-4). The MMAS-4 has been widely validated in various populations and demonstrated acceptable reliability, with a Cronbach’s alpha value indicating satisfactory internal consistency.. A bivariate analysis was conducted using the non-parametric Spearman’s rho test. The findings indicated a p-value > 0.05 (0.132), suggesting no significant relationship between knowledge and medication adherence. Health workers should therefore not only focus on improving the knowledge of older adults but also consider other factors such as motivation, family support, psychological conditions, and perceptions of treatment. Increasing family involvement in reminding medication schedules or assisting with medication preparation is strongly recommended.