Background: Hepatocellular carcinoma (HCC) is a high incidence and high mortality disease. The choice of cancer treatment is extremely important and involves a high-risk, complex and difficult decision-making process. Although the guidelines use evidence for disease treatment, due to the individual patient factors and tumor stage differences, cancer treatment decisions by patients still lead to uncertainty. Objective: When people lack information or skills, they may make decisions that are not optimal. Clinically, we use educational programs to improve patient knowledge but there's no relevant knowledge scale that can be used as an assessment tool. Therefore, it is necessary to develop a convenient and usable knowledge scale. Methods: Based on research purposes, literature review and what physicians believe patients need to know about liver cancer, we built a liver cancer knowledge scale. Results: The total number of participants is 102, of which 66 are male and 36 are female. There is satisfactory internal consistency reliability 0.745, test-retest reliability 1.0 and construct validity were noted CVI 0.96. There was adequate overall evidence for convergent (p = 0.001) and discriminatory validity (p < 0.005). Conclusions: This knowledge scale can provide hepatocellular carcinoma before and after treatment evaluation whether patients have sufficient knowledge.