Developing efficient and stable catalysts for energy conversion processes such as alkaline oxygen evolution reaction is one of the key measures to solve the energy shortage problems. During alkaline oxygen evolution, several electrocatalysts would undergo structural reconstruction from the pre‐catalyst state to the real‐catalyst state. The structural reconstruction may modify the quantity and characterizations of the active sites, thus affecting the configuration and adsorption strength of the reaction key intermediates, which directly influence the activity and stability of the electrocatalysts. Understanding the structural transformation chemistry is essential for the rational design of highly efficient and stable electrocatalysts. In this review, we have deeply discussed the role and regulation strategies of structural reconstruction. Then, on this basis, we described some characterization technologies to probe the structural reconstruction of catalysts during alkaline OER. Finally, we put forward some views on the future research direction of this vital field. The structural reconstruction of electrocatalysts is strongly correlated with their alkaline OER performance and stability. Understanding structural reconstruction chemistry is crucial for the rational design of electrocatalysts. This review gives an overview of the role, regulating strategies, and characterization technologies of structural reconstruction, which open a door for researchers to design high‐performance electrocatalysts.