Semiconductor devices are provided. The semiconductor devices may include an active pattern on a substrate. The active pattern may include a first source/drain region and a second source/drain region. The semiconductor devices may also include a bit line electrically connected to the first source/drain region, a first connection electrode electrically connected to the second source/drain region, and a capacitor on the first connection electrode. The capacitor may include a first electrode, a second electrode, and a dielectric pattern between the first and second electrodes. A lower portion of the dielectric pattern may overlap a top surface of the first connection electrode, and the first electrode may extend on an upper portion of a sidewall of the first connection electrode.