Thermoresponsive and degradable hydrogels are considered promising materials for the development of smart drug delivery carriers that can be applied in the human body. However, the synthesis of a thermoresponsive degradable hydrogel with desirable properties is challenging. Here, we prepared thermoresponsive degradable copolymers and hydrogels by radical copolymerization of 2-methylene-1,3-dioxepane and N,N-dimethylacrylamide. The obtained polymers exhibited low critical solution temperature-type phase separation and a swelling-deswelling behavior. Under alkaline conditions (pH 11.3), these materials degraded and turned into water-soluble oligomers. In addition, the hydrogels self-degraded in PBS due to the decreased pH of the inner hydrogel. The prepared thermoresponsive degradable polymers and hydrogels have potential applicability as stimuli-responsive drug delivery carriers and cell culture scaffolds.