Microrobots driven by bio-actuators have been attracting extensive attention and research interest. However, they can only work in a liquid environment, greatly restricting their practical applications. In this work, we applied the newly developed biomolecular artificial muscle actuator to break this limitation and designed a microrobot aiming to move at the air-water interface. This microrobot was made up of SU-8 and PDMS and driven by photo-patterned artificial muscles. Its 3D microstructure was origami folded from a double-layer structure machined through lithography, without costly 3D micromachining processes. The results preliminarily demonstrated the feasibility of the fabrication and the moving principle of the proposed microrobot.