The invention relates to an oxide ceramic base / NAO composite friction material used in a brake of a medium or high-grade car and a preparation method thereof. In the composite friction material, mixed fibers comprise aramid fibers, potassium titanate fibers and silicon, magnesium and calcium oxide ceramic fibers; aedelforsite or mineral fibers and copper fibers are used as the enhancement and conduction fibers; phenolic resin is used as the organic bonding agent; pure oxide ceramics, such as Al2O3, ZrO2, MgO, CaO and the like, are used as the abrasives; solid lubricant, sulfide, graphite coke and the like are used as the abrasion resistant lubricants; and sodium bicarbonate is used as the blowing agent and pairing antioxidant, and barium sulfate inorganic filler is used as the function and toughening filler. The ceramic base / NAO organic friction material mainly maintains the unique performance of the asbestos friction material, remakably lowers the noise, reduces the abrasion possibility, and is beneficial to prolonging the service life of a brake disc, there by being a novel green (less-dust) low-noise environmentally-friendly friction material.