A board mating connector which includes a signal contact unit, the board mating connector comprising: a signal contact unit; a ground contact unit which has a ground hollow portion, wherein the signal contact unit is inserted into the ground hollow portion; and a dielectric unit which is disposed between the signal contact unit and the ground contact unit, wherein the signal contact unit includes: a housing which has a housing insertion hole of which one side is open; a contact portion which has a contact portion insertion hole of which the other side is open; and a signal spring which is inserted between the one side of the housing insertion hole and the other side of the contact portion insertion hole, wherein one side of the housing is partially inserted into the contact portion insertion hole, and in a state in which the signal spring is compressed, an inner side of the contact portion comes into contact with an outer side of the housing so that the housing and the contact portion are electrically connected, characterized in that the contact portion includes a contact portion protrusion which protrudes from an inner wall of the other end of the contact portion; two or more contact portion slits which are elongated to one side of the contact portion from the other end thereof along a circumference of the contact portion, and wherein, in a state in which the signal spring is restored, the contact portion protrusion is inserted into a housing groove formed in a ring shape along a circumference of the housing. a signal contact unit; a ground contact unit which has a ground hollow portion, wherein the signal contact unit is inserted into the ground hollow portion; and a dielectric unit which is disposed between the signal contact unit and the ground contact unit, wherein the signal contact unit includes: a housing which has a housing insertion hole of which one side is open; a contact portion which has a contact portion insertion hole of which the other side is open; and a signal spring which is inserted between the one side of the housing insertion hole and the other side of the contact portion insertion hole, wherein one side of the housing is partially inserted into the contact portion insertion hole, and in a state in which the signal spring is compressed, an inner side of the contact portion comes into contact with an outer side of the housing so that the housing and the contact portion are electrically connected, characterized in that the contact portion includes a contact portion protrusion which protrudes from an inner wall of the other end of the contact portion; two or more contact portion slits which are elongated to one side of the contact portion from the other end thereof along a circumference of the contact portion, and wherein, in a state in which the signal spring is restored, the contact portion protrusion is inserted into a housing groove formed in a ring shape along a circumference of the housing. a housing which has a housing insertion hole of which one side is open; a contact portion which has a contact portion insertion hole of which the other side is open; and a signal spring which is inserted between the one side of the housing insertion hole and the other side of the contact portion insertion hole, wherein one side of the housing is partially inserted into the contact portion insertion hole, and in a state in which the signal spring is compressed, an inner side of the contact portion comes into contact with an outer side of the housing so that the housing and the contact portion are electrically connected, characterized in that the contact portion includes a contact portion protrusion which protrudes from an inner wall of the other end of the contact portion; two or more contact portion slits which are elongated to one side of the contact portion from the other end thereof along a circumference of the contact portion, and wherein, in a state in which the signal spring is restored, the contact portion protrusion is inserted into a housing groove formed in a ring shape along a circumference of the housing.