Abstract: The target of the present study is to estimate the in vitro genotoxic potential of the volatile-anaesthetic halothane (Narcotan7) as well as the protective effect of vitamin A, as an antioxidant. To achieve this task, the alkaline single cell gel electrophoresis (comet assay) was applied as the extent of DNA fragmentation in rabbit lymphocytes that were exposed in vitro to halothane at concentrations of 0.1 or 1.0 mM for 10 and 30 min, respectively. The obtained results elucidated that anaesthetic halothane induced a significant increase in DNA damage that shown by comet DNA concentration and its tail length. The recorded elevation of DNA damage was clearly correlated with halothane concentration as well as the period of exposure. To mend the deleterious effect of halothane on DNA, 25 rabbits were orally received vitamin A (8000 IU kg-1 body weight) for 15 days prior to in vitro halothane exposure. Vitamin A administration induced a significant repairing effect in lymphocytes-damaged DNA due to halothane exposure, comparing with the non-administrated group. The genotoxic effect of halothane might be attributed to its property as an oxidative agent capable to accumulate oxygen free radicals inside the cell and producing DNA damage. Thereby, the antioxidant property of vitamin A might counteract the hazardous effect of anaesthetic halothane. It is concluded that there is a great need of vitamin A intake for patients undergoing surgical operations with halothane anaesthesia and as a prophylactic therapy for the operation room personnel to antagonize the possible genotoxic effect of halothane.