To provide a polymer gel and a polymer gel sheet, which have sufficient tackiness (pastability) to an adherend such as glass or metal plates, can easily be peeled off the adherend and reutilized, and have sufficient pastability and reworkability.

A polymer gel contains a polymer of an urethane (meth)acrylate having two or more methacryloyl groups in one molecule, and a polyol compound, and has dynamic viscoelasticity in which the value of a dynamic loss elastic modulus G" at 25°C measured in a temperature dispersion at a frequency of 1 Hz is in the range of 1.0×10³ to 1.0×10⁴ Pa, and the loss tangent tanδ is <0.05.