A multicentric, double-blind and randomized clinical study was conducted on a total of 54 patients with hyperlipidemias type IIa, IIb and IV in order to compare the effectivity and tolerance of two hyperlipemiant drugs: Binifibrate and Gemfibrozil. The treatment had a length of six months, performing clinical and analytical controls at: baseline, 1 month, 2 months, 4 months and 6 months. Both drugs showed a very good tolerance and the following results were obtained: Total cholesterol: Binifibrate -21.9%, Gemfibrozil -20.5%; Triglycerides: Binifibrate -48.6%, Gemfibrozil -43.27%; HDL: Binifibrate +18.2%, Gemfibrozil -12.8%; LDL: Binifibrate -24.3%, Gemfibrozil -22.8% VLDL: Binifibrate -48%, Gemfibrozil -43.2%; Apo A: Binifibrate +133.5%, Gemfibrozil +108.1%; Apo B: Binifibrate -59.7%, Gemfibrozil -46%. Both treatment were very effective, although the greater increase produced by Binifibrate on Chol-HDL, with a statistically significant difference versus the increase produced by Gemfibrozil, must be highlighted.