A method for attenuating aerodynamic noise from a landing gear may include researching a start point of a shear layer as a flow field characteristic of a region in the vicinity of an original shape of the landing gear, and adding a plate-shaped object in the vicinity of the start point, changing the start point to an edge portion of the plate-shaped object to make the shear layer farther from the original shape. Another method for attenuating aerodynamic noise from a landing gear may include researching a static pressure and an airflow velocity in a region in the vicinity of the landing gear as a flow field characteristic of the region, and adding a plate-shaped object covering a surface of the landing gear which is different from a surface facing an upstream side in an airflow direction, increasing the static pressure in the region to reduce the airflow velocity.