The present invention provides a stereoscopic display apparatus, which comprises: a grating lens comprising a plurality of grating lens units; a 2D display apparatus disposed in the range of a focal distance of the grating lens; a spacing glass disposed between the 2D display apparatus and the grating lens; and at least one lens array disposed neighbor with the spacing glass and between the 2D display apparatus and the grating lens, for converging light emitted from the 2D display apparatus so that the focal distance of the grating lens in the stereoscopic display apparatus is shortened, and therefore a depth of the spacing glass is reduced, wherein the lens array comprises a plurality of lens units being one-by-one correspondence to the grating lens units. By the solution provided above, the present invention reduces the depth and weight of the stereoscopic display apparatus.