Abstract “End-of-life” is a difficult conversational topic in East-Asian culture, even among patients and doctors. In 2016, the “Law on Advance Medical Decisions for End-Stage Patients,” with the so-called “Advance directive (AD),” was enacted in South Korea. Unlike other solid cancers, breast cancer patients have a longer period of survival due to many novel treatments. This study aimed to investigate the acceptance rate of issuing AD and potential barriers to its completion in patients with cancer, including breast cancer (BC). We conducted a cross-sectional descriptive survey of metastatic or recurrent cancer patients visiting Korea University Anam Hospital oncologic department. The primary end point was the rate of completing AD on doctors' suggestion. Written interview was conducted to understand the perceptions and factors influencing patients' decision. The total sample of 77 patients was analyzed in August, 2018 (29 BC and 48 non-BC patients). The median age was 66.0 years, and duration since diagnosis to suggestion of AD was 56.4 months. The mean follow-up time of physicians who suggested AD was 27.1 months. Of 77 patients, 52 (67.5%) agreed to write AD. Of 29 BC patients, 23 (79.3%) agreed to complete AD, while only 29 of 48 (60.4%) non-BC patients did so. BC patients who agreed to write AD had older median age, shorter duration since cancer diagnosis, and shorter duration of follow up than those who refused [age 61 vs. 59 yrs p 0.34, diagnosis duration 61.30 vs. 70.63 p 0.40, follow-up period 22.67 vs. 24.13 p 0.64]. Non-BC patients who completed AD had younger age, longer duration since diagnosis, and longer follow-up period [age 68 vs. 71 p 0.67, diagnosis duration 33.1 vs. 33.2 p 0.20, follow-up period 18.0 vs. 16.9 p 0.25]. However, all the differences were statistically insignificant due to small sample size. The survey showed that patients who agreed to issue AD had relatively high education and were more religious [college graduates 34.6% vs. 16%, respondents with a religion 63.4% vs. 56%]. Of the respondents who completed AD, 42 (80.8%) reported a fare understanding of the concept of hospice palliative care. 21 (40.4%) patients reported understanding AD system “well” or “very well”. Most patients got information about the system from conventional social media like TV and newspaper, followed by their physician [33 (42.9%) and 27 (35.1%)]. Decision on the preparation of advanced life care was mainly by the patients themselves, followed by the spouse and children [38(49.3%), 16(20.1%) and 11(14.3%), respectively]. Reason for writing AD was diverse, including “to leave my own will, not guardian's” (40.4%), “because my doctors recommended it” (36.5%), “to avoid suffering from meaningless treatment” (26.9%), and “to ease the economic burden on the family” (11.5%). The two major reasons for refusal were “needing more discussion with family” (40.0%) and “lack of understanding of the system” (36%). In this study, we identified that BC patients are more likely to accept AD than other types of cancer patients. Highly educated and religious patients tended to accept AD without hesitation. Better education and information shared through media and conversation with doctors might improve understanding of the AD system in Korean cancer patients. Citation Format: Kim JW, Park KH. Advance directives in Korean cancer patients: Preliminary analysis [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P5-14-01.