At present, people’s health awareness is increasing, and there are many people who have annual medical checkups, but there are many cases of people who have normal medical checkups but suddenly found to have cancer, and most of them are already in the middle and late stages of cancer. The real reason is the incorrect method of medical checkup. Let’s say, from Beijing to Nanjing, walking, bicycle, high-speed train or airplane can all be used, but the effect is different. It is the same reason for medical checkups. Different organs use different and targeted examination methods to achieve good results. As we all know, cancer is not formed in one day. Obviously, the most important reason for the sudden discovery of cancer is the misconception that physical examination can replace cancer examination. It is important to choose the right method for cancer prevention physical examination. Ordinary physical examination is not a substitute for cancer examination. Cancer examination is different from ordinary physical examination, and different methods of physical examination need to be chosen, and different and targeted examination methods are used for different organs to achieve good results. General physical examinations are only routine examinations, which have nothing to do with cancer screening, and the results cannot diagnose cancer with certainty at all. As we all know, routine health checkups are very simple, such as urine routine, blood routine, B-ultrasound, ECG, etc. These are not specific to cancer, and their results are normal and cannot be considered cancer-free at all. Cancer tests are all different according to different organs, and even if cancer tests are targeted, their results are still relative, not absolute. Besides, not all cancer tests have their own effective screening methods, and only some of them have clear effective screening methods at present. Therefore, for medical checkup packages, there should be some additions and subtractions, which can be made according to one’s age, gender, occupation, physical condition and other conditions. Gastrointestinal tumors such as esophageal cancer, stomach cancer and colorectal cancer are not considered as routine items in medical checkups because of the long preparation time, therefore, endoscopy should be preferred for digestive tract, gastroscopy for esophagus and stomach, and colonoscopy for colorectum is the current gold standard, as long as no abnormality is found in the examination, generally gastroscopy every 3 years and colonoscopy every 5 years are sufficient. However, many people currently use X-ray chest X-ray for lung cancer screening, but it is actually of little value because the heart, ribs and other structures block the display of lung lesions, and small nodules are also difficult to be detected; breast cancer screening requires physical examination, breast ultrasound and mammogram. Breast cancer screening requires a combination of physical examination, mammography and mammogram, rather than just using infrared instruments to screen for breast tumors, which are difficult to detect in the early stage. To sum up, besides finding the right way to check and prevent cancer, it is necessary to choose a regular specialized hospital for early examination and early treatment, and to maintain a healthy lifestyle and strengthen physical exercise to prevent cancer before it happens.