In protein structure, knot is a vital part. Structures that contain a knot formed by the path of the polypeptide backbone represent some of the most complex topologies observed in proteins. Detecting these knots, we hope to find out some information or chances to cope with protein malfunction or abnormalities. There are some state of the art algorithms to find knot in a protein structure e.g. KNOT [10], In this paper, we present an algorithm to find most density region of protein structure to reduce the complexity of knot finding procedure in a protein.