Disclosed is a collision energy absorbable steering column of a vehicle, which includes a steering shaft having an upper end connected to a steering wheel and a lower end connected to a rack-pinion mechanism; an interior tube for surrounding the steering shaft; an exterior tube for surrounding the interior tube; a wire block assembly fixed to a mounting bracket so as to absorb collision energy by wire deformation when a vehicle crashes against an object; the mounting bracket for supporting the exterior tube, the mounting bracket being fixed to a chassis of the vehicle, the mounting bracket having at least one side rail and at least one wire-assembling hole through which a wire is inserted so as to assemble the mounting bracket with the wire block assembly; and a plate bracket coupled to the mounting bracket by forcibly fitting the plate bracket together with the wire block assembly in the mounting bracket.