In recent years, the generation, transport, and harvesting of hot carriers in surface plasmon (SP) enhanced metal nanostructures have been extensively and deeply studied. Among them, a new photoelectric conversion mechanism based on electronic tunneling and thermal emission effect, combined with planarization manufacture and complementary metal oxide semiconductor (CMOS) compatible integration, is expected to be an alternative scheme for silicon-based infrared photoelectric detection. At present, these detectors are mainly used in metal-semiconductor Schottky junction photovoltaic devices, which have weak photoelectric response. In this paper, a novel photoconductive device based on metal-silicon composite disordered nanostructures is reported. Due to the localized hot spot effect of the disordered surface plasmon and the significant photoconductivity gain of the multiple interdigital metal semiconductor metal (MSM) structures, the broad-band strong photoelectric response of the silicon sub-band gap is obtained experimentally. Finally, the photocurrent responsivity of the hot carrier mediated multiple interdigital MSM devices is as high as 2.50 A/W at 1310 nm.