The invention discloses a process for manufacturing a large-radius neutron absorbing laminate with an end face angle of 45 degrees. The method includes the following steps: a, clipping an aluminum plate; b, polishing a filling contact surface of the aluminum plate; c, performing bending process on the aluminum plate; d, manufacturing an absorbing layer pressing die; e, arranging the absorbing layer pressing die on a 80T four-column hydraulic press; f, using ethyl alcohol to clean the absorbing layer pressing die; g, evenly pasting a Teflon protective film on an arc forming surface of a forming upper die; h, performing Vaseline coating; i, putting the aluminum plate in a lower die forming groove, coating the aluminum with glue; j, putting boron carbide filling in the lower die forming groove, and then performing pre-pressing through a stainless steel roller; k, closing the dies, and keeping a pressure; l, performing static curing; and m, removing the die, and completing manufacturing of the neutron absorbing laminate. Through the steps the process can effectively produce arc neutron absorbing laminates, can be effectively used for production and processing of large-radius neutron absorbing devices.