Lymphedema, a debilitating and chronic condition, is considered to be one of the most distressing adverse effects of cancer treatment. The purpose of this study was to understand the practice patterns in lymphedema care and identify predictors influencing those patterns among oncology nurses, with a focus on advanced practice nurses. Random and purposive sampling was utilized to recruit 238 oncology nurses who completed the Web-based study. Participants included advanced practice nurses (nurse practitioners and clinical nurse specialists), nurse navigators/case managers, staff nurses, and directors/managers/coordinators. Data focused on perceived knowledge of and perceived competence in risk reduction, treatment, and self-management of lymphedema and practice patterns in lymphedema care. Actual knowledge of lymphedema care was evaluated. Descriptive, comparative, and regression analyses were performed. The study showed that perceived knowledge and perceived competence were highly correlated. Perceived competence was a predictor of practicing lymphedema care. Advanced practice nurses scored in the midrange for perceived knowledge and perceived competence in risk reduction and self-management, but obtained lower scores in perceived knowledge and perceived competence for treatment. The odds of advanced practice nurses delivering lymphedema care were less than those of staff nurses. This study identifies gaps and opportunities for advanced practice nurses to play an important role in providing lymphedema care, an essential aspect of cancer survivorship.