Warfarin drug have prominent effects on the blood vessels. One of the important effect was calcifications of blood vessel wall, so the present study focused on the investigation on the role of watery ginger root extract in processing the histological changes in the blood vessels after treated with warfarin for 30 days. The results after treated time with warfarin showed weak tunica intima in the wall of blood vessels, interaction or trading between tunica intima and tunica media without internal elastic lamina in the small artery, irregular shape of fibers and appeared as small piece in tunica adventitia, while the results in the group after treated with warfarin and ginger showed the tunica intima was normally, prominent thin internal elastic lamina under the tunica media which separated between tunica intima and tunica media and normal tunica adventitia that composed of loose connective tissue without any histological changes. Consequently the ginger can be used as improvement material for treatment side effects of warfarin.