The relation between the nonlinear coefficient and the geometry parameters is derived in PCF of TIR type with triangle cladding. The curves showing this relation are presented. The relation between the nonlinear coefficient and the wavelength of the light propagating in PCF is also deduced. The curve about the relation of the nonlinear coefficient and the wavelength shows that this type of PCF has a very high nonlinear coefficient at the short-wave band,which can be potentially applied in many aspects.