A solid electrolytic capacitor with a protective structure, which includes stacked capacitor elements electrically connected to the positive and negative terminal. A packaging material such as synthetic resin is used to encapsulate the capacitor elements, the positive terminal, and the negative terminal. Before packaging, a protective layer is formed by a colloid material, which covers the main body of the capacitor that includes the capacitor elements, the positive terminal, and the negative terminal. The protective layer provides a better seal and relieves the external pressure exerting on the capacitor during the packaging process. The protection prevents structural damage to the capacitor's main body while reducing the risk of short-circuits and excessive current leakage.