There are five known viruses that can cause viral hepatitis A, B, C, D and E. Hepatitis E virus (HEV) infection can lead to acute jaundice type hepatitis, the majority of patients give good after the disease, the course of about 1 to 2 months. Older hepatitis E mostly manifests as biliary hepatitis, with an extended recovery period. Only a very small number of patients develop heavy hepatitis and have a poor outcome. It should be noted that chronic hepatitis B patients should pay special attention to the prevention of hepatitis E virus infection. Overlapping hepatitis E on top of hepatitis B virus (HBV) infection often leads to deterioration of liver function and development of severe hepatitis, resulting in acute or subacute liver failure, poor outcome and high mortality. According to domestic and foreign literature, the incidence of heavy hepatitis in chronic hepatitis B patients with overlapping HEV infection is 27-32%, while the incidence of heavy hepatitis with HBV infection alone is only 4-6.3%. In patients with severe hepatitis B and E overlapping infections requiring treatment, not only is it difficult to treat due to severe liver damage, but some will also develop various complications of heavy hepatitis, which increases the suffering of patients and also adds a heavy economic burden. Therefore, it is important for hepatitis B patients to actively prevent HEV infection. Patients with hepatitis B should be alerted to combined hepatitis E infection when the following conditions occur: sudden appearance of acute hepatitis-like manifestations such as fatigue, nausea and vomiting, hypothermia, deepening jaundice, etc. during the stable phase of liver function, liver biochemical indexes of ALT > 500 U/L, and serum bilirubin (TBil) significantly higher than the normal value. When there are above manifestations, hepatitis E antibody (anti-HEV) should be tested promptly, if anti-HEV (+) both suggest overlapping hepatitis E virus infection. At this time, hospitalization, bed rest, close observation of changes in the condition, testing the changes in the biochemical indicators of liver function, to prevent further deterioration of the condition. The transmission route of HEV is different from that of hepatitis B virus, which is mainly transmitted through the digestive tract. Therefore, the main preventive measures are to pay attention to personal dietary hygiene, wash hands before meals, and avoid eating in restaurants with poor sanitary conditions and using unhygienic tableware. In China, there are many patients with chronic hepatitis B. Prevention and timely detection of overlapping infections of hepatitis E can help reduce the deteriorating activity of chronic hepatitis and the death rate, and prevention should be advocated to avoid the occurrence, early detection and timely treatment.