The invention discloses an elliptical airy vortex beam generator based on a metasurface and a beam generation method thereof, the generator is provided with a silicon dioxide substrate, the substrate is provided with a plurality of nano-columns, the nano-columns are distributed in a matrix mode, the length of each nano-column is Wx, the width of each nano-column is Wy, and the rotation angle of each nano-column is alpha; the light beam generation method comprises the steps that the light beam generator generates an elliptical Airy vortex light beam under vertical incidence of circularly polarized light, and the polarization conversion rate and the transmissivity of a transmission light field are changed by controlling the geometric size and the rotation angle of the nano-column. According to the invention, a plurality of nano columns made of monocrystalline silicon are arranged on the silicon dioxide substrate to construct a metasurface device, and compared with a traditional spatial light modulator, the device is simple in structure, lighter in weight and smaller in size on the premise that complex light beams conforming to expectation can be generated, and convenience is brought to generation of the complex light beams in practical application.