A wireless module comprising: a substrate; a first ground pattern disposed on a first main surface of the substrate and a second ground pattern disposed on a second main surface of the substrate, the first and second ground patterns being electrically connected to each other, the first ground pattern having a first exposed portion and the second ground pattern having a second exposed portion, the first exposed portion and the second exposed portion being disposed at positions facing each other on the substrate, the exposed portions (21, 22) being portions that are not covered with a resist and exposed to the outside in ground patterns; a first antenna disposed between one end of the substrate and the first ground pattern, the first antenna including a grounding part and a first power feeding part, the grounding part being connected to the first ground pattern, the first power feeding part configured to be fed with a first signal; a second antenna disposed between another end of the substrate opposite to the one end of the substrate and the first ground pattern, the second antenna including a second power feeding part configured to be fed with a second signal; a base plate that is conductive, the base plate including a first opposed portion that faces the first antenna, a second opposed portion that faces the second antenna, and a third opposed portion that faces the second ground pattern and is short-circuited to the first and second ground patterns; wherein the base plate has, on the third opposed portion, a short-circuit point (54, 55) at which the base plate and the first and second ground patterns are short-circuited to each other via the first exposed portion and the second exposed portion, the short-circuit point (54, 55) is disposed at a position nearer to the first opposed portion than to the second opposed portion, characterized in that the wireless module further comprises a fastening member that is conductive and configured to fasten the substrate and the base plate to each other, the fastening member is a conductive screw and is disposed on the short-circuit point, the base plate is short-circuited to the first ground pattern by being short-circuited to the first exposed portion on the first main surface via the fastening member and the short-circuit point which is a threaded hole, and the short-circuit point is a protrusion being directly connected to the second exposed portion on the second main surface, such that the base plate is short-circuited to the second ground pattern. a substrate; a first ground pattern disposed on a first main surface of the substrate and a second ground pattern disposed on a second main surface of the substrate, the first and second ground patterns being electrically connected to each other, the first ground pattern having a first exposed portion and the second ground pattern having a second exposed portion, the first exposed portion and the second exposed portion being disposed at positions facing each other on the substrate, the exposed portions (21, 22) being portions that are not covered with a resist and exposed to the outside in ground patterns; a first antenna disposed between one end of the substrate and the first ground pattern, the first antenna including a grounding part and a first power feeding part, the grounding part being connected to the first ground pattern, the first power feeding part configured to be fed with a first signal; a second antenna disposed between another end of the substrate opposite to the one end of the substrate and the first ground pattern, the second antenna including a second power feeding part configured to be fed with a second signal; a base plate that is conductive, the base plate including a first opposed portion that faces the first antenna, a second opposed portion that faces the second antenna, and a third opposed portion that faces the second ground pattern and is short-circuited to the first and second ground patterns; wherein the base plate has, on the third opposed portion, a short-circuit point (54, 55) at which the base plate and the first and second ground patterns are short-circuited to each other via the first exposed portion and the second exposed portion, the short-circuit point (54, 55) is disposed at a position nearer to the first opposed portion than to the second opposed portion, characterized in that the wireless module further comprises a fastening member that is conductive and configured to fasten the substrate and the base plate to each other, the fastening member is a conductive screw and is disposed on the short-circuit point, the base plate is short-circuited to the first ground pattern by being short-circuited to the first exposed portion on the first main surface via the fastening member and the short-circuit point which is a threaded hole, and the short-circuit point is a protrusion being directly connected to the second exposed portion on the second main surface, such that the base plate is short-circuited to the second ground pattern.