A structured beam generation device based on beam shaping and a method adopting the device are provided. Linearly polarized beam emitted by a laser sequentially passes through an electro-optic intensity modulator, a half-wave plate, and a first beam expander, and then enters a first polarization beam-splitting prism to be transmitted and reflected. The transmitted beam sequentially passes through a beam shaper, an optical delay line, and a first reflector to form a parallel ring-shaped beam to be transmitted by a second polarization beam-splitting prism. The reflected beam sequentially passes through an electro-optic phase modulator, a second reflecting mirror, and a second beam expander, and is then reflected by the second polarization beam-splitting prism and combined with the transmitted beam into a beam, which is then adjusted by a polarizing plate have consistent polarization direction, and is finally focused at a focal plane by a focusing lens for interference.