A method of fabricating a deep trench capacitor includes the steps as follows. Firstly, a substrate having a trench therein is provided. Then, a bottom electrode is formed in the substrate around the trench. Later, a capacitor dielectric layer is formed to surround an inner sidewall of the trench. After that, a first conductive layer is form to fill up the trench. Subsequently, a material layer is formed on the substrate. Later, a hole is formed in the material layer, wherein the hole is directly above the trench. Finally, a second conductive layer is form to fill in the hole.