A contact probe of a testing head of a testing apparatus of electronic devices comprises respective end portions adapted to contact respective contact pads and a body essentially extended in a longitudinal direction between the end portions, at least one end portion comprising an insert made of a first conductive material having a hardness being greater than a second conductive material making the contact probe which is supported by a section of the end portion, the section being made of the second conductive material and being shaped in a complementary way with respect to the insert and having respective abutting surfaces facing and adhering to respective abutting surfaces of the insert.