In many countries the power systems are going to move toward creating a competitive structure for selling and buying electrical energy. This paper presents a new method based on Modified Firefly Optimization (MFO) algorithm to Distribution Feeder Reconfiguration (DFR) problems at the distribution networks considering Wind Turbines (WTs). The objectives consist of minimization of costs and losses of distributed system. The effectiveness of the proposed algorithm is demonstrated through IEEE 32 bus standard test systems. Also, regarding the uncertainties of the new complicated power systems such as the active and reactive loads in addition to the wind speed variations effectively, in this paper for the first time, the DFR problem is investigated in a stochastic environment by the use of probabilistic load flow technique based on Point Estimate Method (PEM). The feasibility of the MFO algorithm and the proposed DFR is demonstrated and compared with the solutions obtained by other approaches and evolutionary methods.