Blade structures are widely employed in aerospace engineering, such as wings and rotor blades. Blade structures are usually thin-shell structures, which are very easy to excite low-frequency breathing vibration and result in structural damage. This paper takes a blade structure as the research object and considers the optimization design for maximizing its first eigenfrequency (i.e. the breathing vibration frequency). The topology optimization formulation for eigenfrequency of the blade structure is therefore established. Under the volume constraint, the distribution of the webs in the cavity of the blade structure is designed. By employing ANSYS software for modal analysis and experiments for vibration tests of the blade structures before and after optimization, the results show that the first four eigenfrequencies of the blade structure are all improved dramatically, which achieves the purpose for manipulating the eigenfrequency of the blade structure. The structural safety issue caused by the low-frequency breathing vibration of the blade structure is alleviated by improving its first-order eigenfrequency, which provides a reference for relevant structural optimization design of eigenfrequencies.