The utility model relates to the technical field of flange gasket positioning devices, and discloses an automatic positioning type flange gasket. The automatic positioning type flange gasket comprises a gasket body and a soft metal layer. The circle of soft metal layer is fixedly installed on the outer circumference of the gasket body, and circular cutting lines concentrically ringed with the soft metal layer are arranged on the soft metal layer. The automatic positioning type flange gasket is reasonable and compact in structure and convenient to use, during installation, the redundant part on the periphery of the soft metal layer is stripped off along the circular cutting lines according to the size of the circumference defined by bolts on a flange, the external diameter of the left soft metal layer is right clamped in the circumference defined by the bolts, manual position adjusting is not needed, and the gasket body can be aligned very easily and cannot deviate.