A lens edging system of the present invention includes: an edger configured to perform edging of a spectacle lens using an edging tool; a shape measurement device configured to measure an edging shape of a circumferential edge of the spectacle lens after edging by the edger; a memory part configured to store information regarding a reference shape of the edging tool used by the edger; a shape comparing and judging part configured to compare a measurement result obtained by the shape measurement device and a reference shape of the edging tool specified from the information stored in the memory part, and judge necessity/non-necessity for exchanging the edging tool based on a comparison result; and an information output part configured to output information regarding necessity for exchange when the shape comparing and judging part so judges.