In recent years, chimeric antigen receptor T-cell (CAR-T) therapy has shown a certain value in the treatment of malignant hematological tumors, especially for patients with relapsed/ refractory B-cell lymphoma. Currently, 18F-FDG PET-CT has proved its great clinical values in the diagnosis and treatment of lymphoma. There are relatively few studies using 18F-FDG PET-CT to evaluate B-cell lymphoma treated by CAR-T therapy, but some good results have also been achieved. This paper reviews the current research progress of 18F-FDG PET-CT in CAR-T therapy for B-cell lymphoma.