The antifertility potency of Marijuana had been revealed in our recent study. Hence, investigating its effect on other body systems became necessary. This study was setup to determine the effects of inhaled marijuana and Vitamin C on serum lipids and serum proteins of male rats using the following parameters; Total Cholesterol level, Triglycerides level, High density Lipoprotein level, Low density Lipoprotein level, Albumin level, Total Bilirubin level, Direct Bilirubin level and Total Protein level. This study was carried out with a total of forty (40) male wistar rats randomly divided into four groups of ten (10) rats per group. Group 1 was the control and was treated with distilled water, group 2 was the low dose group (exposed to marijuana smoke for 5 minutes daily), group 3 was the high dose group (exposed to marijuana smoke for 10 minutes daily) and group 4 was the high dose + vitamin C group (exposed to marijuana smoke for 10 minutes and orally gavaged with vitamin C at 2.8 mg/kg body weight daily). The animals were sacrificed on the 29th day and blood was collected by cardiac puncture into plain bottles. The collected blood was allowed to clot and centrifuged at 300rev per minutes for 20mins. The serum was collected with the aid of a micropipette for the biochemical analysis of lipid profile and serum protein according to George, 2009 and Bjorsten et al., 2007. The results were as follows; Serum albumin and Total bilirubin levels were significantly decreasing (p<0.05) down the groups. Direct bilirubin level was significantly increased (p<0.05) in the low dose marijuana (LMJ) treated group when compared with the control group and was significantly decreased in the high dose marijuana + vitamin C (HMJ+Vit C) treated groups when compared with control and high dose marijuana (HMJ) treated groups respectively. Total protein was significantly decreased (p<0.05) in the high dose Marijuana + vitamin C (HMJ+Vit C) treated groups when compared with control group and within the other groups. Total cholesterol levels was significantly decreased (p<0.05) in the high dose Marijuana + vitamin C (HMJ+Vit C) treated groups when compared with control group. High density lipoprotein levels was significantly decreased (p<0.05) in the high dose Marijuana + vitamin C (HMJ+Vit C) treated groups when compared with control group. Triglycerides level was not significantly different in the low dose Marijuana (LMJ) treated group and high dose Marijuana + vitamin C (HMJ+Vit C) treated groups when compared with control group and within the groups. Low density lipoprotein level was significantly increased (p<0.05) in the high Marijuana + vitamin C (HMJ+Vit C) treated groups when compared with control group. This study has shown that inhaled Marijuana negatively affected various liver metabolic pathways leading to decline in albumin levels; elevated Bilirubin and lipid levels.Co-administration of oral Vitamin C was found to lower serum Bilirubin levels. Levels of total Cholesterol, High Density Lipoproteins and Tryglycerides were also lowered in rats treated with Vitamin C. It is possible that the use of Vitamin C may be beneficial in individuals at risk of cardiovascular diseases.