The invention belongs to the technical field of film, and provides a carbon nanotube/nanometer fiber conductive composite film, and a preparation method thereof. According to the preparation method, one-dimensional nanometer non-woven fabric prepared through electrostatic spinning technology is taken as a supporting layer; carbon nanotubes are crosslinked on the supporting layer as a separating layer, so that the conductive film with a net shaped pore structure formed through interweaving of the on-dimensional nanometer material is constructed. The film pore diameter is controllable from microfiltration to ultrafiltration range, the film can be flat film, or hollow fiber film, or coiled film, and is controllable. The main advantages and beneficial effects are that: the preparation steps are simple; excellent permeability and mechanical strength are achieved; excellent hydrophilic performance and electricity conductivity are achieved; and large scale production applications are easy torealize.