By applying fuzzy set theory to optimal power flow with transient stability constraints and considering the practical features of power system, the traditional transient stability constrained optimal power flow model is modified, the rotor angles constraint, voltage constraint and the objective function are fuzzily processed, and the TSCOPF fuzzy model is established by max-min methods. Besides, a collaborative evolutionary particle swarm optimization algorithm which is suitable for large-scale nonlinear optimization problem is established to solve the transient stability constrained optimal power flow. In order to enhance the efficiency of the optimization algorithm, considering the model’s characteristics, a transient stability simulation early terminated strategy and a master-slave parallel technology are applied to the algorithm, and the algorithm is parallel processed using MATLAB toolbox. The test results on the New England 10-machine system demonstrate the proposed method is effective and feasible.