The invention discloses a method a method for reducing arbitrary Gauss projection deformation based on a maximum projection deformation least standard. For better controlling maximal projection deformation of a project, this kind of projects should be researched through a strict computing method according to a principle of minimizing the maximal projection deformation. The method comprises the steps of firstly determining a distance Ym' between a central meridian and a projection gravity center position of a measuring area, solving deltalW and deltalE according to a known Ym before meridian movement, and furthermore determining a projection gravity center position Yg; then obtaining the distance between a new central meridian and an original meridian according to the projection gravity center position Yg, and obtaining the geodetic longitude M of the new central meridian through geodetic inversion; and finally setting the central meridian to M, converting the coordinate of the measuring area to the central meridian M for performing projection calculation, thereby reducing the arbitrary Gauss projection deformation. Furthermore the invention defines the maximal application range of the method.