Abstract: Objective A Preliminary test is to be performed to test the friction properties of monocrystal ceramic bracket and polycrystalline ceramic bracket compared with metal bracket of the same size. Methods The maximum static friction force and the average dynamic friction of monocrystal ceramic bracket, polycrystalline ceramic bracket and metal bracket combined with two kinds of metal arch-wires were tested by a universal testing machine. Results The friction produced by the combination of monocrystal ceramic bracket or polycrystalline ceramic bracket with two kinds of arch-wires was greater than the metal bracket. The metal bracket had smallest frictional force of three kinds of brackets. The monocrystal ceramic bracket had smaller frictional force than polycrystalline ceramic bracket. Conclusions The frictional force of monocrystal ceramic bracket and arch-wires is smaller than polycrystalline ceramic bracket，but is greater than metal bracket combined with arch-wires.