Despite the significant progresses made in the reduction of mortality due to cardiovascular diseases, they are still the primary cause of death in many countries and hyperlipidemia is an important causal agent of cardiovascular diseases. Probiotics are food supplements containing live microbes which balance the flora of the digestive system and produce positive effects in the host body. L.acidophilus is a beneficial bacterium used in the production of probiotic products .The aim of this study is to evaluate the effects of consumption of milk containing L.acidophilus on serum lipid trends of rats fed high lipid diet. This is an experimental study in which 30 male albino Wistar rats with a body weight of 200±15 gr. were randomly allocated to two groups of treatment and control each containing 15 rats which were adapted to a high lipid diet (11.74%) and water containing 25% milk within a week. Rats in both groups received high lipid diet and water containing 25% milk for 60 days with the exception that rats in the treatment group received water containing L. acidophilus at a level of 109 CFU/rat/day throughout the experiment. Independent t-test revealed that at a level of α= 0.05, mean levels of total cholesterol and LDL-C of rats in the treatment group was significantly lower than the control group (p