The invention discloses a small horizontal axis wind turbine for driving blades and a power generation method thereof. The resistance of the blades largely reduces the efficiency of a wind driven generator. Two spokes on the same one side are respectively fixed with two ends of one blade mounting shaft; the blade mounting shafts and the blades form rotating pairs; the blades are divided into two parts with different chord lengths by the axes of the blade mounting shafts; stop rods are respectively fixed on the inner sides of two blade mounting shafts; the stop rods include first cross bars, vertical rods, second cross bars and stop rings; the stop rings are fixed at the bottom ends of the second cross bars; included angles between the second cross bars and the spokes are 5-10 degrees; the directions of the stop rings of the two stop rods are opposite; and an upper hub is supported on a rotor of the generator, and is connected with the rotor of the generator through a clutch. The blade mounting shafts divide the blades into unequal parts to force the blades to deflect; and the stop rods control the deflecting angles of the blades to reach the optimal windward area, so that the efficiency of the generator is improved.