Objectives <p>To characterize the lived experiences and unmet needs of nutritional education among colorectal cancer patients undergoing chemotherapy based on the Knowledge-Attitude-Practice model, thereby informing the development of evidence-based nutritional intervention programs.</p> Methods <p>A descriptive qualitative study was conducted using purposive sampling. From January to March 2022, semi-structured interviews were performed with 17 colorectal cancer patients undergoing chemotherapy at five tertiary Grade A general hospitals in western China. All interviews were audio-recorded, transcribed verbatim, and thematically analyzed. Two researchers independently coded the interviews using NVivo 12, and directed content analysis was employed to inductively summarize and refine themes.</p> Results <p>Five barriers to effective nutritional education were identified: (1) Lack of nutrition education knowledge, (2) Lack of evidence-based nutrition beliefs, (3) non-standardized nutritional practices, (4) Barriers to receiving nutrition education, and (5) Diversified needs for nutrition education.</p> Conclusions <p>Colorectal cancer patients undergoing chemotherapy reported suboptimal nutritional education experiences and multifaceted needs, highlighting persistent challenges. Healthcare providers should comprehensively assess patients’ educational experiences, deliver multimodal interventions addressing diverse needs, enhance education accessibility and acceptability, and strengthen nutritional awareness to mitigate malnutrition risks.</p> Practice Implication <p>Our results provide insights for cancer patient nutrition educators to better help colorectal cancer chemotherapy patients, emphasizing the need to educate them about the knowledge, behaviors, beliefs, and more they have not received. This will enable colorectal cancer chemotherapy patients to receive better nutrition education, reduce their risk of malnutrition, and improve their recovery and quality of life.</p>