The electrochemical oxygen evolution reaction (OER) can be combined with various reactions to fabricate electrochemical energy conversion and storage devices while the slow kinetics and poor mass transfer capability at high current densities are the key constraints to its large‐scale application. Therefore, this review primarily focuses on design and optimization of mass transfer structures of TM‐metal‐based OER catalysts. Nanostructuring, porous design, and the creation of hierarchical architectures have been applied during catalyst synthesis to enhance the surface area and accessibility, thereby improving mass transfer and catalytic OER efficiency. Strategies including doping, substrate invitation, soft/hard templating have been utilized to accelerate mass transfer as well as the ion/electron conduction efficiency for the overall improvement of OER performance of the catalysts. These developments underline the critical role of advanced material design in achieving high‐performance OER catalysts and highlight the potential of TM‐based materials in cost‐effective and scalable applications.