The invention discloses an all-solid-state arsenate electrode and a manufacturing method thereof. The electrode comprises a silver wire, a silver particle intermediate layer wrapping the surface of the silver wire, and a silver arsenate sensitive film wrapping the surface of silver particles. The manufacturing method comprises the following steps of firstly, electroplating the silver particles onthe surface of silver wire; and then, using an electrochemical mode to wrap the silver arsenate sensitive film on the surface of the silver particles. The manufacturing method is simple. The size of the manufactured all-solid-state arsenate electrode is small, sensitivity is high and a response is fast. And arsenate ion concentration can be rapidly detected in a water environment. The electrode isused with a solid reference electrode in a matching mode and can be used for the long-term in situ monitoring of an arsenate ion content.