The objective of the present invention is to provide a crystallization device and a crystallization process for obtaining (meth) acrylic acid with higher purity without causing leakage of a crude solution by preventing complete clogging in a crystallization tube from occurring. The device for crystallizing (meth)acrylic acid according to the present invention is characterized in comprising a crude (meth)acrylic acid solution supply part, a crystallization tube, a heat medium supply tube, a heat medium discharge tube, a storage part of a crude (meth)acrylic acid solution passed through the crystallization tube, a tube for circulating and supplying the crude (meth)acrylic acid solution to the supply part from the storage part, and a pump for circulating and supplying the crude (meth) acrylic acid solution to the supply part from the storage part; and further comprising a pressure meter in the circulate-supply tube; wherein the device is used for carrying out dynamic crystallization in a batch manner by circulating the crude (meth)acrylic acid solution to flow the crude solution downward along the inner wall of the crystallization tube in a coating film-like state.