An EEPROM includes a substrate, a first semiconductor layer and a second semiconductor layer formed on the substrate. The first semiconductor layer is isolated from the second semiconductor layer by a trench. A first source and a first drain are located at two opposing sides of the first semiconductor layer. A first dielectric layer is formed on the first semiconductor layer, and a first floating gate is formed on the first dielectric layer. A second source and a second drain are located at two opposing sides of the second semiconductor layer. A second dielectric layer is formed on the second semiconductor layer, and a second floating gate is formed on the second dielectric layer. The first floating gate and the second floating gate are electrically connected.