To reduce the number of process to obtain a light guide body, having a high quality, at a low cost by a method wherein a matrix, having a plurality of recessed of predetermined configuration and array, is manufactured and a resin layer is formed on the surface having the recesses, then, the resin layer is separated from the matrix after curing the resin layer.

A matrix 10, having a plurality of recesses 11 of a predetermined configuration and array, is manufactured and a resin layer 12 is formed on the material 10. Next, energy is given to cure the resin layer 12 to transfer the shape of recesses 11 on the matrix 10 precisely and form projections, having sharp edge, on the light guide body. Then, the resin layer 12 is separated from the matrix 10 and a light guide body 14, having the projections 13, is obtained. The width of the projection is specified so as to be 5-300μm and the height of the same is preferable to be about one half of the width. The energy, given to the resin, is preferably of either one of light, heat or both of light and heat whereby ultraviolet ray curing type resin, for example, can be utilized. The matrix 10 can be used many times when it is manufactured once whereby the number of process and cost can be reduced.