Three‐dimensional carbon fiber/epoxy resin composites are prepared, which have either three‐axis or five‐axis fabrics (3D‐3A or 3D‐5A) in four woven gauges and four specimen thicknesses. The impact properties of these 3‐D composites are studied. The results show that when the woven gauge is decreased by 1mm, the impact perforation energies of 3D‐3A and 3D‐5A are increased by 12.6J and 5.4J, respectively, and the impact perforation energy is increased by 38J when the specimen thickness is increased by 1mm. The initial impact energy of 3D‐3A is higher than that of 3D‐5A, but the propagation energy and ductility index of 3D‐5A with a woven gauge larger than 3.75mm are higher than those of 3D‐3A. In addition, the impact properties, the impact damage area and the strength loss after impact test are better when the woven gauge is decreased.