Objective : We designed this study to analyse the Natural Standard methodology and apply the results to new study and evaluation methods. Methods : We investigated the main stream of complementary and alternative medicine (CAM), the methodology of Natural Standard, guideline in CAM, and concrete 35 cancer-related herbs and dietary supplements in 98 ones. Results : There are 35 graded herbs and supplements associated with cancer in natural standard contents: 9 foods, 17 herbs, 7 amino acids, enzymes and vitamins, and 2 herbal mixture formulas. Most of them get a grade of C: unclear or conflicting scientific evidence. Conclusion : Natural Standard aims to provide high-quality, reliable information about CAM therapies to clinicians, patients, and healthcare institutions. The more demands for and use of CAM grows, the more the needs for related studies increases. According to this international and multidisciplinary collaborative effort, we have to develop how to study and evaluate the results. We need guidelines in association with the evidence and recommendations of CAM.