To provide a method of manufacturing a cross prism by which the occurrence of flare or the like can be reduced without scattering light incident in a cross prism at an adhering layer and video of good quality can be obtained by carrying out good color synthesis and further to provide the cross prism thus manufactured.

The adhering layer 5 is formed by carrying out curing treatment of an adhesive 55 in one lot and four triangular prisms 1, 2, 3, 4 are bonded and fixed to form a cross prism 10. Thereby curing treatment of the adhesive 55 can be carried out in one lot in the same curing processing condition to obtain formation of the homogeneous adhering layer 5. The occurrence of flare or the like can be reduced without scattering light incident in a cross prism 10 at the adhering layer and video of good quality can be obtained by carrying out good color synthesis to achieve a manufacturing method of the cross prism 10.