Tuberculosis (TB) has recently re-emerged as a major public health problem in Thailand. As a consequence of the HIV epidemic in the country, the TB burden has been rising in terms of both morbidity, and mortality which have tremendous socioeconomic impact. However, a study of the cost of various anti-TB drugs in Thailand has never been conducted. A specific aim of this study was to compare the total provider costs of delivering services to different types of TB patient in four zonal TB centers located in the east, northeast, north, and south of Thailand. This aim was accomplished by calculating the unit costs of TB treatment services at these TB centers during the year 1996-1997. All units of the zonal TB centers were classified into 5 cost center categories: treatment units, laboratory units, radiology units, pharmaceutical units, and administrative/supportive units. The results showed that the average total provider cost of multidrug resistant TB (MDR TB) patients was fl 89,735.49 which was the highest of any type of patient and was 17 times higher than the cost of smear-negative TB cases; this finding was attributed to the high cost of anti-TB drugs for MDR TB cases (fl 65,870), some 95 times higher than the cost for smear-negative cases. Total provider costs were highest in the northeastern region TB centers and lowest in the southern centers for every type of TB patient: smear-negative TB cases (fl 7,727 vs fl 3,916), newly smear positive TB cases (fl 12,539 vs fl 7,020), TB with AIDS cases (fl 15,108 vs fl 8,369), re-treatment TB cases (fl 16,679 vs fl 9,696), and MDR TB cases (fl 102,330 vs fl 82,933). The information from this study may be useful when reviewing the role, function, and cost structure of each TB center in Thailand in order to establish a strategic plan for effective TB control.