Abstract: A conservation integral photoelasticity method is provided for determination of stress intensity factors in fracture mechanics.The displacement gradients in the expression of the concervative integral are expressed in terms of stress components.Then,the conservative integral can be evaluated by the interference fringe patterns in photoelastic experiments.Finally,the stress intensity factor will be determined by the J K-Ⅰ relation in fracture mechanics.Due to the path independent property of conservative integral,the difficuties encountered in the methods of mono parameter,bi parameter and multi parameter can be overcomed by this one.The agreements between the results given by this method and those obtained from the boundary collocation method are satisfactory.