Due to the fact that conventional available antituberculosis susceptibility tests are time consuming and laborious, new methods which are easy to use, give the results in a short time and cost-effective are needed. The aim of this comparative study was to evaluate different methods used in determining the susceptibility of ycobacterium tuberculosis to primary drugs. Totalyy 50 M. tuberculosis isolates were tested for susceptibility to streptomycin, isoniasid, rifampicin and ethambutol using four different methods. The results of BACTEC 460TB method, manual MGIT method and proportion method in Löwenstein-Jensen media were compared with the results of agar proportion method which is accepted as standard reference method. Agreement between BACTEC 460 method and agar proportion method was 100% for all drugs. Agreement between MGIT method and agar proportion method was 100% for streptomycin and rifampicin and 98% for isoniasid and ethambutol. One isolate resistant to isoniasid and another isolate resistant to ethambutol in agar proportion method were found susceptible with MGIT method. Agreement between Löwenstein- Jensen proportion method and agar proportion method was 90% for streptomycin, isoniasid and rifampicin and 94% for ethambutol. In Löwenstein-Jensen proportion method, major errors were obtained for isoniasid in three isolates, for ethambutol in one isolate, for streptomycin in two isolates and for rifampicin in two isolates. The median duration of the tests were 20.2, 5.8, 7.1, and 28 days for agar proportion method, BACTEC 460TB method, manual MGIT method and Lowenstein-Jensen proportion method, respectively. In conclusion, there were no statistically significant differences in susceptibility test results between the reference agar proportion method and the other methods, namely BACTEC 40TB, manual MGIT and Löwenstein-Jensen proportion method. However, it is conspicuous that the duration of Löwenstein-Jensen proportion method is longer than those of other three methods and may cause major test errors. Manual MGIT method can also be used as a rapid and easy method if it is well standardized.