The invention relates to a bionic finger with controllable flexibility. The flexible and controllable bionic finger includes bionic skin poured into finger shape, electromagnetic coil, strain gauge sensor, magnetorheological fluid, sealing boss, rigid support body, finger control box, nail seat, sealant, sealing gasket, set screw; the bionic finger with controllable compliance The control circuit is mainly composed of three operational amplifiers with high common-mode rejection ratio amplifier circuit, digital-to-analog conversion and single-chip microcomputer chip principle circuit, crystal oscillator circuit, reset circuit, and power supply circuit; The flexible and controllable bionic finger It is a soft and controllable finger based on magnetorheological fluid, which can realize the continuous and controllable "liquid-solid" state transition of magnetorheological fluid; when applying force to the bionic finger, it can ensure that the deformation of the finger is within a certain range Inside, it will not be too large to damage, nor too small to be flexible. In order to improve the ability of the robot to coordinate with the outside world.