Within a short period of liver cancer surgery, or if cancer cells are still present after liver cancer surgery, alpha-fetoprotein may be 40 μg/L, but both are abnormal. The normal level of alpha-fetoprotein, a tumor marker for liver cancer, is <25 μg/L. In patients with liver cancer, alpha-fetoprotein is significantly elevated. In postoperative liver cancer patients, if the liver cancer is completely removed by surgery, the alpha-fetoprotein may still be higher than normal for a short period of time, one and a half months after surgery, because it takes time to metabolize and remove the alpha-fetoprotein from the bloodstream. If the liver cancer surgery fails to completely remove the cancer cells or there is recurrence and metastasis after the surgery, the alpha-fetoprotein will also be higher than the normal level. Patients with higher than normal value of alpha-fetoprotein after liver cancer surgery should have a timely recheck.