A sensor of an electromagnetic induction type coordinate input device, comprising: a first loop coil group, in which plural first loop coils are disposed in a first direction, each of the first loop coils including a first extraction line portion composed of a first line and a second line formed in parallel with each other, and a first loop portion continuously connected to the first and second lines of the first extraction line portion and having a shape that surrounds a predetermined area; and a second loop coil group, in which plural second loop coils are disposed in a second direction perpendicular to the first direction, each of the second loop coils including a second extraction line portion composed of a third line and a fourth line formed in parallel with each other, and a second loop portion continuously connected to the third and fourth lines of the second extraction line portion and having a shape that surrounds a predetermined area, wherein an area occupied by the first loop portions of the first loop coil group and the second loop portions of the second loop coil group define a position detection area, and characterized in that one of the first line or the second line of one of the first loop coils is connected to (ii) a line of the second loop portion of one of the second loop coils, within the position detection area, to form a common extraction line with (ii), and the other of the first line or the second line of said one of the first loop coils having the common extraction line is disposed in parallel with and close to the common extraction line, wherein at least a portion of the first loop portions of the first loop coils which extend to intersect with the first direction is formed on a first surface of a substrate, the first extraction line portions are formed on a second surface on a side opposite to the first surface of the substrate, and the first extraction line portions and the first loop portions are connected to each other via through holes provided in the substrate; and at least a portion of the second loop portions of the second loop coils which extend to intersect with the second direction is formed on the second surface of the substrate, and a connection between said one of the first line or the second line of one of the first loop coils and (ii) a line of the second loop portion of one of the second loop coils is formed on the second surface of the substrate. a first loop coil group, in which plural first loop coils are disposed in a first direction, each of the first loop coils including a first extraction line portion composed of a first line and a second line formed in parallel with each other, and a first loop portion continuously connected to the first and second lines of the first extraction line portion and having a shape that surrounds a predetermined area; and a second loop coil group, in which plural second loop coils are disposed in a second direction perpendicular to the first direction, each of the second loop coils including a second extraction line portion composed of a third line and a fourth line formed in parallel with each other, and a second loop portion continuously connected to the third and fourth lines of the second extraction line portion and having a shape that surrounds a predetermined area, wherein an area occupied by the first loop portions of the first loop coil group and the second loop portions of the second loop coil group define a position detection area, and characterized in that one of the first line or the second line of one of the first loop coils is connected to (ii) a line of the second loop portion of one of the second loop coils, within the position detection area, to form a common extraction line with (ii), and the other of the first line or the second line of said one of the first loop coils having the common extraction line is disposed in parallel with and close to the common extraction line, wherein at least a portion of the first loop portions of the first loop coils which extend to intersect with the first direction is formed on a first surface of a substrate, the first extraction line portions are formed on a second surface on a side opposite to the first surface of the substrate, and the first extraction line portions and the first loop portions are connected to each other via through holes provided in the substrate; and at least a portion of the second loop portions of the second loop coils which extend to intersect with the second direction is formed on the second surface of the substrate, and a connection between said one of the first line or the second line of one of the first loop coils and (ii) a line of the second loop portion of one of the second loop coils is formed on the second surface of the substrate.