It is possible for leukemia to come back during taking chemotherapy drugs and there is a possibility of leukemia resistance. Chemotherapy for leukemia is mainly used to kill tumor cells through chemotherapy drugs, so that patients can achieve a state of remission. However, chemotherapeutic drugs can only kill most of the leukemia cells and have no effect on some dormant leukemia cells, so it is possible that the tumor cells lurking in the body may multiply again, leading to the symptoms of leukemia to flare up again, causing the relapse of leukemia after chemotherapy. Patients should follow the doctor’s advice and take active chemotherapy; eat a healthy diet and have a regular rest; they should also have regular rechecks; and finally, they should stay away from harmful substances, such as paint and white trash, which are some of the factors for the relapse of leukemia. If there is any discomfort, it is recommended to go to the hospital in time.