Anti-tuberculosis have up set the out come of this disease, however undesirable effects principally hepatotoxicity remain of ten the ransom of this therapy success. 28 observations of hepatic toxicity in allergology pneumo service in military hospital of Tunisia during 5 years (1996-2001) among 321 tuberculosis. Hepatic toxicity is observed in 28 cases, 21 cytolytics, 3 cholostatics and 4 mixt. 3 decease (death) have been observed. Anti-tuberculosis medicament (medecine) are sometimes this cause of many undesirable effect, which can be miner or major and even cases of decease. So that we have to take an interest at time and specialty to follow recommandation which are more and more codified.