A tire inner pressure measurement system comprising: a detector that detects the inner pressure of a tire and an acquisition apparatus that acquires data regarding the inner pressure of the tire detected by the detector, wherein the detector comprises: a resonance circuit that includes: a capacitive sensor having capacitance changed according to a change in an inter-electrode distance by the inner pressure of the tire; and a detection-side antenna unit formed by a coil, the antenna unit being connected to the capacitive sensor, the acquisition apparatus comprises: an acquisition-side antenna unit that is formed by a coil that acquires resonant waveforms of the resonance circuit including the capacitive sensor; a driving unit (52, 53) that applies electromotive force to the detection-side antenna unit; and a signal amplification unit that amplifies the resonant waveforms; CHARACTERISED BY: the coil of the resonance circuit being obtained by winding a conductive wire around a coil material; the coil of the acquisition-side antenna unit being obtained by winding a conductive wire around a coil material; the acquisition-side antenna unit generating electromotive force in the detection-side antenna unit by electromagnetic induction; the capacture sensor being charged by the electromotive force and the detection-side antenna unit; a division unit that divides a predetermined number of waveforms among the amplified resonant waveforms into one pulse; a conversion unit that converts a period from rise to fall of the pulse into a voltage value; and a pressure calculation unit that calculates the inner pressure of the tire based on the voltage value converted by the conversion unit. a resonance circuit that includes: a capacitive sensor having capacitance changed according to a change in an inter-electrode distance by the inner pressure of the tire; and a detection-side antenna unit formed by a coil, the antenna unit being connected to the capacitive sensor, the acquisition apparatus comprises: an acquisition-side antenna unit that is formed by a coil that acquires resonant waveforms of the resonance circuit including the capacitive sensor; a driving unit (52, 53) that applies electromotive force to the detection-side antenna unit; and a signal amplification unit that amplifies the resonant waveforms; CHARACTERISED BY: the coil of the resonance circuit being obtained by winding a conductive wire around a coil material; the coil of the acquisition-side antenna unit being obtained by winding a conductive wire around a coil material; the acquisition-side antenna unit generating electromotive force in the detection-side antenna unit by electromagnetic induction; the capacture sensor being charged by the electromotive force and the detection-side antenna unit; a division unit that divides a predetermined number of waveforms among the amplified resonant waveforms into one pulse; a conversion unit that converts a period from rise to fall of the pulse into a voltage value; and a pressure calculation unit that calculates the inner pressure of the tire based on the voltage value converted by the conversion unit. an acquisition-side antenna unit that is formed by a coil that acquires resonant waveforms of the resonance circuit including the capacitive sensor; a driving unit (52, 53) that applies electromotive force to the detection-side antenna unit; and a signal amplification unit that amplifies the resonant waveforms; the coil of the resonance circuit being obtained by winding a conductive wire around a coil material; the coil of the acquisition-side antenna unit being obtained by winding a conductive wire around a coil material; the acquisition-side antenna unit generating electromotive force in the detection-side antenna unit by electromagnetic induction; the capacture sensor being charged by the electromotive force and the detection-side antenna unit; a division unit that divides a predetermined number of waveforms among the amplified resonant waveforms into one pulse; a conversion unit that converts a period from rise to fall of the pulse into a voltage value; and a pressure calculation unit that calculates the inner pressure of the tire based on the voltage value converted by the conversion unit.