This article quoted Institution Change Theory to reveal the necessary of holding a hearing, in the approval process of modification to Urban planning conservation zone, to resolve disputes and improve the degree of consensus among the interests of all parties.And to enhance the objectivity of modification to Urban planning conservation zone, the authorities should establish the examination mechanism of the evaluation index to do some examination in this case. Moreover, without approval of rezoning, the authorities should apply for the plot ratio transfer system or some related systems as due compensation, in the situation of the limitation of land use is beyond special sacrifice boundaries, so as to meet the law standard.