The present invention discloses a liquid-driven nano-porous actuator and the application thereof, and belongs to the field of nano material actuators. According to the present invention, by changing the content of the liquid in the nano-porous material, the interface between the surface liquid of the nano-porous material and air is exchanged between flat and curved states, so as to change the compressive stress acting on the nano-porous material from the surface tension of the liquid and change the elastic deformation of the nano-porous material, thus driving the nano-porous material to contract and expand in a reversible manner and further realizing driving performance. The actuator features simple and easy implementation and environmental-friendly effect without the need of external physical excitation signals (light, magnetic field, electricity or heat), complicated external excitation process, conversion of electric, magnetic, and light energy, chemical or electrochemical process, or toxic, harmful or corrosive chemical substances, and it is especially suitable for bio-robot, medical and aerospace fields.