A biological characteristic information detection device for being arranged on an electronic device, wherein the detection device comprises: a pressure detection module comprising a cantilever beam and a pressure sensor, wherein the pressure sensor is fixed on a surface of the cantilever beam, the cantilever beam comprises an elastic arm and a fixed base, the fixed base is fixed in the electronic device, and the elastic arm is suspended in the air; and a photoplethysmography detection module arranged on the elastic arm and configured to detect a PPG signal of a user when the user presses the electronic device, wherein when the user presses the electronic device, a pressure signal applied to the electronic device by the user is transmitted to the cantilever beam through the PPG detection module, so that the pressure sensor detects the pressure signal, and the pressure signal and the PPG signal are used to detect biological characteristic information of the user; the biological characteristic information detection device further comprising: an elastic member arranged on one opposite side of the PPG detection module facing towards the electronic device for sensing a pressing direction of the user and configured to limit a movable distance of the PPG detection module within a preset range so as to limit a force applied by the user within a pressure range required by the biological characteristic information detection, and an elastic force of the elastic member is controlled within the pressure range required for the biological characteristic information detection by controlling an elastic parameter of the elastic member; wherein the elastic member is fixedly connected to the PPG detection module through a sliding holder; the detection device further comprising: a second holder fixedly connected to the sliding holder, the second holder being internally provided with a second cavity, the sliding holder and the elastic member sliding in the second cavity along a second direction, and the second direction being perpendicular to the elastic arm. a pressure detection module comprising a cantilever beam and a pressure sensor, wherein the pressure sensor is fixed on a surface of the cantilever beam, the cantilever beam comprises an elastic arm and a fixed base, the fixed base is fixed in the electronic device, and the elastic arm is suspended in the air; and a photoplethysmography detection module arranged on the elastic arm and configured to detect a PPG signal of a user when the user presses the electronic device, wherein when the user presses the electronic device, a pressure signal applied to the electronic device by the user is transmitted to the cantilever beam through the PPG detection module, so that the pressure sensor detects the pressure signal, and the pressure signal and the PPG signal are used to detect biological characteristic information of the user; the biological characteristic information detection device further comprising: an elastic member arranged on one opposite side of the PPG detection module facing towards the electronic device for sensing a pressing direction of the user and configured to limit a movable distance of the PPG detection module within a preset range so as to limit a force applied by the user within a pressure range required by the biological characteristic information detection, and an elastic force of the elastic member is controlled within the pressure range required for the biological characteristic information detection by controlling an elastic parameter of the elastic member; wherein the elastic member is fixedly connected to the PPG detection module through a sliding holder; the detection device further comprising: a second holder fixedly connected to the sliding holder, the second holder being internally provided with a second cavity, the sliding holder and the elastic member sliding in the second cavity along a second direction, and the second direction being perpendicular to the elastic arm. an elastic member arranged on one opposite side of the PPG detection module facing towards the electronic device for sensing a pressing direction of the user and configured to limit a movable distance of the PPG detection module within a preset range so as to limit a force applied by the user within a pressure range required by the biological characteristic information detection, and an elastic force of the elastic member is controlled within the pressure range required for the biological characteristic information detection by controlling an elastic parameter of the elastic member; wherein the elastic member is fixedly connected to the PPG detection module through a sliding holder; the detection device further comprising: a second holder fixedly connected to the sliding holder, the second holder being internally provided with a second cavity, the sliding holder and the elastic member sliding in the second cavity along a second direction, and the second direction being perpendicular to the elastic arm.