To evaluate the effect of pravastatin on both lipid and glucose metabolism, twenty-two consecutive dyslipidemic patients treated with pravastatin at 10 mg/day for one year were enrolled in this study. The meal test, which consisted of 115 g of cookies (energy 560 kcal; glucose 75 g; protein 7 g; fat 24 g), was conducted before and after one year of treatment. Insulin resistance was assessed by the homeostasis model assessment of insulin resistance (HOMA-IR), by the area under the IRI curve (AUC-IRI), and by the formula AUC-IRI × AUC-PG. After one year of treatment with pravastatin, the plasma glucose (PG), immunoreactive insulin (IRI) and C-peptide levels were unchanged after fasting and at 120 minutes after the meal test; however, PG, IRI and C-peptide levels at 60 minutes after the meal were all significantly decreased from baseline (p < 0.05). AUC-IRI and AUC-IRI × AUC-PG were also significantly decreased (p < 0.05). HOMA-IR was reduced by 26.8%, but the reduction was not significant. The triglyceride (TG) level was decreased after fasting and increased at 60 and 120 minutes after the meal test, but not significantly. This study demonstrated that pravastatin not only reduced serum lipids, but also improved the glucose metabolism, including insulin resistance, of dyslipidemic patients.