The aim of this research work was to evaluate the effect of low dose of Thuja occidentalis for three months on rabbit. To achieve this aim histopathology of heart, liver, stomach and kidney tissues of control groups as well as Thuja occidentalis treated groups with and without carbon tetrachloride was carried out on rabbits. Liver function test of the group injected CCl4 was also done. Our study demonstrated that minor harmful effects were found in liver and kidney tissues injected carbon tetrachloride but no major toxicity was observed in any of the examined tissues due to potent anti-oxidant potential of active constituents present in Thuja occidentalis.