Even in a case in which a comb-teeth shape is provided at an end portion of a cover covering an opening in a magnetic shield case that accommodates a magnetic sensor, the present disclosure obtains a magnetic sensor device and a housing therefor capable of maintaining the strength of a comb-teeth portion. The magnetic sensor device and the housing therefor include: a comb-teeth portion in which protrusions are formed in the shape of comb teeth along an intersecting direction intersecting a conveying direction, the comb-teeth portion being formed at an end portion of a cover with respect to the conveying direction, the cover covering an opening in a magnetic shield case that accommodates a magnetic sensor; and support members formed on a lateral face of the magnetic shield case, the support members supporting the protrusions on the side opposite to the conveying path.