A pen detection system is provided which does not require an integrated circuit dedicated to a large display panel. A pen detection system 1 includes an integrated circuit 3a and an integrated circuit 3b. The integrated circuit 3a is connected to a first partial column electrode group 2xGa to acquire a first column level distribution indicating a level distribution of a pen signal in the first partial column electrode group 2xGa and is connected to a first partial row electrode group 2yGa to acquire a first row level distribution indicating a level distribution of the pen signal in the first partial row electrode group 2yGa. The integrated circuit 3b is connected to a second partial column electrode group 2xGb to acquire a second column level distribution indicating a level distribution of the pen signal in the second partial column electrode group 2xGb and is connected to a second partial row electrode group 2yGb to acquire a second row level distribution indicating a level distribution of the pen signal in the second partial row electrode group 2yGb. The pen detection system 1 derives a column direction position of a pen based on the first and second column level distributions and derives a row direction position based on the first and second row level distributions.