Objective To explore the diagnosis and treatment of Mycobacterium tuberculosis infection in a child with severe β Mediterranean anemia after allogeneic hematopoietic stem cell transplantation (allo-HSCT). Methods The clinical data of a child with severe β mediterranean anemia who had Mycobacterium tuberculosis after allo-HSCT were retrospectively analyzed. The pertinent literatures were reviewed. Results Six-year-old girl with mediterranean anemia was infected by Mycobacterium tuberculosis after allo-HSCT. After anti tuberculosis treatment by HRZE (isoniazid, rifampicin, pyrazinamide and ethambutol), the condition was improved. Conclusion It is rare of Mycobacterium tuberculosis infection after allo-HSCT, which needs timely diagnose and treatment.