A memory structure having a floating body is provided, which includes a substrate including an active area and an isolation structure surrounding the active area, a first source/drain region in the substrate in the active area, a first floating body in the substrate above the first source/drain region, a second floating body on the first floating body, a second source/drain region on the second floating body, and a trench-type gate structure in the substrate and beside the first floating body. A method of fabricating a memory structure having a floating body is also provided.