Abstract : Cancer is one of the leading causes of death in the world, oral chemotherapy is an increasingly important treatment option for cancer This study aims to determine the level of adherence to capecitabine and its contributing factors such as sociodemographic characteristics, side effect, and QALY (quality of life) among cancer outpatients. This study was cross sectional study conducted from March to May 2021 at a referral hospital in Yogyakarta. The participant was outpatients with capecitabine treatment, with colorectal or breast cancer in all stages, with a total of 135 patients. This study using the Medication Adherence Rating Scale (MARS) for measuring adherence and the EQ5D-5L dimension for measuring the quality of life. Data collected was analyzed by using SPSS. Correlation between adherence and characteristics of patient analyzed with bivariate analysis using the chi-square test. Patient adherence with capecitabine was 64.44%. There are some factors that are significant associated with adherence of patients like comorbidities, stage of cancer, the regiment of capecitabine, use of traditional medicine, experienced symptom, and quality of life. Meanwhile type of cancer did not have correlation with adherence of patient (p<0.05). Although no absolute adherence to oral capecitabine treatment had been observed, the level of adherence was fair. Health professionals, therefore, need a greater focus in monitoring the involvement of patients with oral treatment regimens. The results underline the importance of intensified multidisciplinary care to enhance adherence to capecitabine.