This work deals with controller design of doubly fed Induction generator based Wind turbine using bacterial foraging optimization technique .The bacterial foraging optimization (BFO) technique is employed to design the controller intended for small damping plant of the DFIG. Wind energy overview and DFIG operating principle along with the equivalent circuit model is adequately discussed in this paper. The best controller for DFIG driven by variable speed Wind turbine using bacterial foraging optimization (BFO) technique and PID controller based Supervisory control are described comparatively in detail. The obtained results are compared for performance enhancement of DFIG and wind energy conversion system. The responses of the DFIG system regarding terminal voltage, current, active ¿reactive power, and DC link voltage are to be observed. At the end, the obtained output is equated with a standard technique for performance improvement of DFIG based wind energy conversion system. The basics about Bacterial Foraging Optimization and Supervisory controller have been included. The mathematical modelling of DFIG and Fitness function are also discussed.