A tester for micromechanical properties of a biological soft tissue, comprising: a support, the support being provided thereon with a sample test platform (21), a pressure test head (22) facing the sample test platform (21) and a drive mechanism driving the pressure test head (22) to move towards/away from the sample test platform (21); a miniature force testing assembly, the miniature force testing assembly comprising a first conduit (31), a first piston (32) actively connected to the first conduit (31) and supporting the sample test platform (21), a second conduit (33), a second piston (34) actively connected to the second conduit (33), a pressure-amplifying platform (35) connected to the second piston (34), and a force sensor (36) for testing the force of the pressure-amplifying platform (35), the first conduit (31) and the second conduit (33) being connected by means of a hose, and the cross-sectional area of the sample test platform (21) being smaller than the cross-sectional area of the pressure-amplifying platform (35). A micro force is amplified using the principle of hydraulic amplification, and a micro displacement is amplified using the principle of lever amplification so as to test the micro force and the micro deformation of a biological soft tissue.