Provided is a memory structure including first and second transistors, an isolation structure, a conductive layer and a capacitor. Each of the first and second transistors includes a gate disposed on the substrate and source/drain regions disposed in the substrate. The isolation structure is disposed in the substrate between the first and second transistors. The conductive layer is disposed above the first and second transistors and includes a circuit portion electrically connected to the first and second transistors and a dummy portion located above the isolation structure. The capacitor is disposed between the first and second transistors. The capacitor includes a body portion and first and second extension portions. The first and second extension portions extend from the body portion to the source/drain regions of the first and the second transistors, respectively. The first and second extension portions are disposed between the circuit portion and the dummy portion, respectively.