Defrosting frozen pork with a low temperature requires a long time and the quality of pork after defrosting becomes an issue. We tried to shorten the defrosting time of pork loin by using an electric field. At the same time we examined the quality of the defrosted meat using pork loin. We also melted ice cubes and measured the pH of melted water. Defrosting was carried out by placing the object between two electrodes, one rod-type and another in plate-type, which were used to create electric fields with three different voltages, 5, 10, and 12 kV. The rate of ice cube defrosting was accelerated when the object was subjected to the electric field. The increased rates at 10 and 12 kV were 25.1% and 28.8%, respectively. A pork loin cube, 20×20×20 mm, was also placed in the electric fields. The times needed to defrost the pork were 62 min in 10 kV and 30 min in 12 kV, compared with 86 min in the control. When the size of the meat was increased to 20×50×100 mm, the times required for complete defrosting were 337 min in 5 kV, 168 min in 10 kV and 165 min (1/2 of the control) in 12 kV. After defrosting the pH of the water declined, 0.39 by 10 kV and 0.89 by 12 kV. The declines of pH may be a result of the formation of nitrogen oxides by the spark in the electric field, which were dissolved into the water. Subjecting pork loin to the electric fields did not seem to have changed the quality of the pork in terms of colour, pH, moisture content, water-holding capacity and the amount of dripping.