A pneumatic pollination device and a method for hybrid rice seed production with a large row ratio are provided. The pneumatic pollination device includes a pneumatic pollination component, a controller, a lifting adjustment component and a four-wheel power chassis. The pneumatic pollination component is mounted at the front part of the four-wheel power chassis through the lifting adjusting component, and the controller is mounted at the upper part of the four-wheel power chassis. The airflow of each pollination pipe respectively acts on the spike part of the male parent row of corresponding hybrid rice, so that the male pollen is separated from stamens and floats to the female compartment. The airflow velocities of the pollination pipes of respective male parent rows are different to ensure that the pollen is conveyed to the main female parent action region.