Objective To assess the rationale for including rifampicin150/isoniazid75/ethambuto/275mg fixed dose, combination oral tablets/3-FDC R150H75E275/ in the WHO Model List of Essential Medicines (WHO EML) for treatment of category II tuberculosis (TB II) and to provide evidence for the updating of national guidelines. Methods We searched Chinese Biomedical Database (CBM, 1978 to 2006), The Cochrane Library, Issue 4, 2006, the Database of Abstracts of Reviews of Effects (1994 to 2006, the Centre for Reviews and Dissemination website), MEDLINE (1950 to 2006), EMBASE (1974 to 2006), BIOSIS Previews (1997 to 2006), websites for grey literature and the references of studies. We applied inclusion and exclusion criteria in assessing the studies we found and eligible studies were graded following an assessment of their quality. Results Thirty-six randomized controlled trials, 4 controlled clinical trials, 11 descriptive studies and 5 WHO/national guidelines were included. Rifampicin (R), isoniazid (H) and ethambutol (E) were used in the ccontinuation phase (CP) of TB II in guidelines of WHO and high tuberculosis (TB) burden countries, but the course of treatment and dosage regimens varied. R, H and E were also widely used in conditions of pulmonary tuberculosis (PTB), extrapulmonary tuberculosis (EPTB) and pulmonary diseases caused by nontuberculous mycobacteria (NTM).Conclusions It is recommended that FDC RHE be included in WHO EML for the treatment of TB II.The suggested dosage ratio of RHE is 1:1:2, which needs to be adjusted based on more solid clinical evidence. High quality clinical studies and systematic reviews on the effectiveness, safety, economics and applicability of WHO and national guidelines and their outcomes in high TB burden countries are needed to guide their updating, promote rational resource allocation and improve cost effectiveness. Alternative drugs or drug combinations with good profile of effectiveness, safety, economics, and applicability for the prevention and treatment of drug-resistant tuberculosis are also needed to be developed.