Background The often poor prognosis associated with cancer necessitates empowering patients to express their care preferences. Yet, the prevalence of Advance Directives (AD) among oncology patients remains low. This study investigated oncologists' perspectives on the interests and challenges associated with implementing AD. Methods A French national online survey targeting hospital-based oncologists explored five areas: AD information, writing support, AD usage, personal perceptions of AD's importance, and respondent's profile. The primary outcome was to assess how frequently oncologists provide patients with information (...) about AD in daily clinical practice. Additionally, we examined factors related to delivering information on AD. Results Of the 410 oncologists (50%) who responded to the survey, 75% (n = 308) deemed AD relevant. While 36% (n = 149) regularly inform patients about AD, 25% (n = 102) remain skeptical about AD. Among the respondents who do not consistently discuss AD, the most common reason given is the belief that AD may induce anxiety (n = 211/353; 60%). Of all respondents, 90% (n = 367) believe patients require specific information to draft relevant AD. Physicians with experience in palliative care were more likely to discuss AD (43% vs 32.3%, p = 0.027). Previous experience in critical care was associated with higher levels of distrust towards AD (31.5% vs 18.8%, p = 0.003), and 68.5% (n = 281) of the respondents expressed that designating a “person of trust” would be more appropriate than utilizing AD. Conclusion Despite the perceived relevance of AD, only a third of oncologists regularly apprise their patients about them. Significant uncertainty persists about the safety and relevance of AD. (shrink)