To provide a practicable lens fastening mechanism of rimless spectacles which is extremely stable in the holding state of lenses and is capable of simplifying its structure.

The following technical means are adopted: Fastening pins crooked like hairpin turns are disposed near both right and left ends of a bridge or the lens side ends of endpieces. The abutting parts of the fastening pins exist in the notches formed in the side parts of the lenses and on the other hand, fitting projections are formed on the projecting end sides which are connected by couplings from these abutting ends and are sharply returned and crooked. These projecting end sides are elastically expanded and are pierced into the fastening holes of the lenses to fit the fitting projections, by which the bridge or the endpieces and the lenses are tightly clamped and grasped and the right and left lenses are connected and held. Accordingly, the structure capable of surely fastening the lenses with the extremely simple structure by ingeniously harmonizing the crooked shape as well as elasticity and rigidity of the metallic materials of the fastening pins is realized.