In this thesis, we design and simulate an isolator based on linear photonic crystal by nonlinear optofluid infiltration. The necessary condition for having asymmetric transmission (optical isolator) for nonlinear structure, is broken symmetry. for the firs time, we do this by infiltrate nonlinear (Kerr) optofluids in selective holes. The results show that, with this passive simple structure we can reach to desirable nonreciprocal transmission rate (27/92dB) at 1550/38nm wavelength. The power of light is 2/4mW. The transmission of light for backward direction at this wavelength is -12/58dB, that is good for passive structure. In addition to the reconfigurable of this isolator, it is integrated cause of its small area. This isolator, designed whit two-dimensional hexagonal lattice photonic crystal; consist of holes in linear silicon. Lattice constant and radius of airs respectively is a=420nm and r=0.3a