A stereo camera device, comprising: a casing; a first imaging portion provided on one of ends of the casing in a longitudinal direction of the stereo camera device, a second imaging portion provided on the other end of the casing in the longitudinal direction; a substrate on which a processing circuit connected to the first imaging portion and the second imaging portion through signal lines (111, 112) is mounted, on which a connector for outputting a signal processed by the processing unit to an external device is placed, and which is provided in the casing; characterized in further comprising at least one partition for dividing an interior of the casing into a plurality of spaces in the longitudinal direction at first intervals using the following equation, f 1 = 150 1 / L 2 + m / M 2 + n / N 2 1 / 2 wherein f1 is a cavity resonance frequency, L, M, N are lengths of the divided spaces and 1, m, n are the number of half wavelengths in the spaces divided in the casing; wherein the first intervals are determined on the basis of the cavity resonance frequency and the number of half wavelengths in the spaces divided in the casing so as to correspond to a frequency band which allows suppression of radiation noise from the signal lines, wherein at least the one partition includes a first partition member provided in an inner wall of an upper surface of the casing in a lateral direction of the stereo camera device, and a second partition member provided on an inner wall of a lower surface of the casing in the lateral direction, the first partition member is connected to a ground wire provided on an upper surface of the substrate through a first ground member, and the second partition member is connected to a lower surface of the substrate through a ground wire provided on a second ground member. a casing; a first imaging portion provided on one of ends of the casing in a longitudinal direction of the stereo camera device, a second imaging portion provided on the other end of the casing in the longitudinal direction; a substrate on which a processing circuit connected to the first imaging portion and the second imaging portion through signal lines (111, 112) is mounted, on which a connector for outputting a signal processed by the processing unit to an external device is placed, and which is provided in the casing; characterized in further comprising at least one partition for dividing an interior of the casing into a plurality of spaces in the longitudinal direction at first intervals using the following equation, f 1 = 150 1 / L 2 + m / M 2 + n / N 2 1 / 2 wherein f1 is a cavity resonance frequency, L, M, N are lengths of the divided spaces and 1, m, n are the number of half wavelengths in the spaces divided in the casing; wherein the first intervals are determined on the basis of the cavity resonance frequency and the number of half wavelengths in the spaces divided in the casing so as to correspond to a frequency band which allows suppression of radiation noise from the signal lines, wherein at least the one partition includes a first partition member provided in an inner wall of an upper surface of the casing in a lateral direction of the stereo camera device, and a second partition member provided on an inner wall of a lower surface of the casing in the lateral direction, the first partition member is connected to a ground wire provided on an upper surface of the substrate through a first ground member, and the second partition member is connected to a lower surface of the substrate through a ground wire provided on a second ground member.