A pressure detection apparatus, comprising: a drive power supply, a differential circuit, a pressure calculation unit and at least one pressure sensor; each pressure sensor comprises a first electrode plate, a second electrode plate, a third electrode plate, a first elastic dielectric layer and a second elastic dielectric layer; the first electrode plate is disposed between the second electrode plate and the third electrode plate; the first elastic dielectric layer is disposed between the first electrode plate and the second electrode plate; the second elastic dielectric layer is disposed between the first electrode plate and the third electrode plate; wherein, one detection capacitor is formed between the first electrode plate and the second electrode plate, and one detection capacitor is formed between the first electrode plate and the third electrode plate; the pressure sensor is connected between the drive power supply and an input terminal of the differential circuit, and an output terminal of the differential circuit is connected to the pressure calculation unit; the pressure sensor is configured to output two detection voltages across two terminals of each of the two detection capacitors (C1, C2) when the first electrode plate is subject to an external pressure caused by a finger or other conductive object; wherein both of the two detection capacitors (C1, C2) change when the first electrode plate is subject to the external pressure; and the differential circuit is configured to output a voltage difference of the two detection voltages; the pressure calculation unit is configured to calculate the pressure according to the voltage difference. each pressure sensor comprises a first electrode plate, a second electrode plate, a third electrode plate, a first elastic dielectric layer and a second elastic dielectric layer; the first electrode plate is disposed between the second electrode plate and the third electrode plate; the first elastic dielectric layer is disposed between the first electrode plate and the second electrode plate; the second elastic dielectric layer is disposed between the first electrode plate and the third electrode plate; wherein, one detection capacitor is formed between the first electrode plate and the second electrode plate, and one detection capacitor is formed between the first electrode plate and the third electrode plate; the pressure sensor is connected between the drive power supply and an input terminal of the differential circuit, and an output terminal of the differential circuit is connected to the pressure calculation unit; the pressure sensor is configured to output two detection voltages across two terminals of each of the two detection capacitors (C1, C2) when the first electrode plate is subject to an external pressure caused by a finger or other conductive object; wherein both of the two detection capacitors (C1, C2) change when the first electrode plate is subject to the external pressure; and the differential circuit is configured to output a voltage difference of the two detection voltages; the pressure calculation unit is configured to calculate the pressure according to the voltage difference.