A touch system comprising: two or more active pens; and a touch display device that comprises: a display panel on which a plurality of touch electrodes is arranged; and a touch circuit configured to supply a driving signal to the display panel, to sense pen touches made by the two or more active pens, based on a signal received in response to the driving signal, wherein one frame period repeatedly includes a display period and a blank period, pen signals output from the two or more active pens are emitted to the display panel in two or more blank periods among a plurality of blank periods in the one frame period, and the touch circuit is configured to sense the pen touches made by the two or more active pens based on the pen signals, wherein the pen signals include a plurality of pen pulses, and among the plurality of pen pulses generated in response to a predetermined operation signal of the touch circuit or driving signal, some pen pulses are in a first state, in which the some pen pulses are in an in-phase relationship with an operation signal of the touch circuit or the driving signal, in a second state, in which the some pulses are in an inverse-phase relationship with the operation signal of the touch circuit or the driving signal, or in a third state, in which the some pulses have a constant value. two or more active pens; and a touch display device that comprises: a display panel on which a plurality of touch electrodes is arranged; and a touch circuit configured to supply a driving signal to the display panel, to sense pen touches made by the two or more active pens, based on a signal received in response to the driving signal, wherein one frame period repeatedly includes a display period and a blank period, pen signals output from the two or more active pens are emitted to the display panel in two or more blank periods among a plurality of blank periods in the one frame period, and the touch circuit is configured to sense the pen touches made by the two or more active pens based on the pen signals, wherein the pen signals include a plurality of pen pulses, and among the plurality of pen pulses generated in response to a predetermined operation signal of the touch circuit or driving signal, some pen pulses are in a first state, in which the some pen pulses are in an in-phase relationship with an operation signal of the touch circuit or the driving signal, in a second state, in which the some pulses are in an inverse-phase relationship with the operation signal of the touch circuit or the driving signal, or in a third state, in which the some pulses have a constant value. a display panel on which a plurality of touch electrodes is arranged; and a touch circuit configured to supply a driving signal to the display panel, to sense pen touches made by the two or more active pens, based on a signal received in response to the driving signal, wherein one frame period repeatedly includes a display period and a blank period, pen signals output from the two or more active pens are emitted to the display panel in two or more blank periods among a plurality of blank periods in the one frame period, and the touch circuit is configured to sense the pen touches made by the two or more active pens based on the pen signals, wherein the pen signals include a plurality of pen pulses, and among the plurality of pen pulses generated in response to a predetermined operation signal of the touch circuit or driving signal, some pen pulses are in a first state, in which the some pen pulses are in an in-phase relationship with an operation signal of the touch circuit or the driving signal, in a second state, in which the some pulses are in an inverse-phase relationship with the operation signal of the touch circuit or the driving signal, or in a third state, in which the some pulses have a constant value.