Fixing device and machining platform

The utility model relates to the technical field of laser processing, in particular to a fixing device and a processing platform. The fixing device comprises a supporting plate structure, a clamping piece, a pressing piece and a first adjusting piece, the clamping piece is in sliding connection with the supporting plate structure, the pressing piece comprises a pressing end and an adjusting end, and the pressing piece is rotationally connected with the clamping piece; the first adjusting piece is connected with the adjusting end and used for adjusting the height of the adjusting end so as to drive the pressing end to ascend or descend. The material is fixed in the horizontal direction through the clamping piece, and the height of the adjusting end of the pressing piece is adjusted through the first adjusting piece, so that the pressing end of the pressing piece fixes the material in the vertical direction, and the material can be well fixed to the supporting plate structure; the machining precision and the ma