In Turkey, between 22.1% and 84.1% of patients with cancer use complementary and alternative medicine (CAM). However, few CAM-related studies have focused on the perspective of oncology nurses. This study aimed to determine the knowledge, attitudes, and practices of Turkish oncology nurses regarding CAM. A descriptive cross-sectional survey of 127 participants was conducted in Ankara, Turkey. A semistructured questionnaire including characteristics, knowledge, attitudes, and practices of oncology nurses toward CAM was administered to participants. We found that more than half of nurses (54.0%) surveyed had no information on CAM modalities. Most oncology nurses (81.1%) used audiovisual media sources to obtain CAM information. Many nurses (81.3%) reported not using any CAM in cancer care, and only 26.8% recommended CAM to patients. Most nurses used CAM to accelerate wound healing (19.7%) and to manage symptoms, including constipation and diarrhea (8.8%) and anxiety (7.9%). Music (52.8%), massage (49.6%), and exercise (48.8%) were stated to be beneficial. Important barriers to use CAM for patients with cancer involved a lack of knowledge (60.6%); needing physician approval to apply any CAM methods to patients (52.1%); legal and institutional issues (47.2%); and limited educational, training, or certificate programs (44.1%). There is a need for increased knowledge about CAM by oncology nurses, considering their vital role in symptom management of patients with cancer. This can be achieved through solving legal and institutional problems, structured and comprehensive education/training programs, and the integration of CAM therapy into cancer care guidelines.