Poly(N, N-dimethylaminoethyl methacrylate) (polyDMAEMA) hydrogels prepared by γ-irradiation showed obvioustemperature-sensitivity in a temperature range of 38-40℃ and pH-sensitivity at pH = 2.5. They also showed clectric responsebehavior although it was not typical. The hydrogels were used in controlled release at different pH, temperature, and electricvoltage. The release rates of methylene blue (MB) from the gels at 52℃ and pH = 1.24 were fatter than those at 20℃ and pH= 10.56, respectively. In addition, the release rate at a field voltage of 5.0 was also faster than that without electric field. Poly (N, N-dimethylaminoethyl methacrylate) (polyDMAEMA) hydrogels prepared by γ-irradiation showed significant temperature-sensitivity in a temperature range of 38-40 ° C and pH-sensitivity at pH = 2.5. They also showed clectric responsebehavior although it was not typical . The release rates of methylene blue (MB) from the gels at 52 ° C and pH = 1.24 were fatter than those at 20 ° C and pH = 10.56, respectively. In addition, the release rate at a field voltage of 5.0 was also faster than that without electric field.