The main aim of the project is to correct the power factor in single phase bridgeless converter. The AC-DC converters is used to improve power quality in terms of power factor correction, reduced total harmonic distortion at input AC mains and precisely regulated DC output. Here we introduce a bridgeless single phase boost converter based on three-state switching cell topology, whose distinct advantages are reduced conduction losses with the use of magnetic elements with minimized size, weight and volume. Boost converters operating in continuous-conduction mode is preferred because reduced electro-magnetic interference levels result from utilization. The principles of interleaved boost can also be employed. The feedback loop introduce from the load to the switching cell is to improve the power factor is also introduces in this paper. These converters are suitable for high power application due to present of auto transformer.