Sudden cardiac arrest is unexpected, which can be fatal. Providing quick assistance to patients with the automated external defibrillator (AED) can reduce the risk of loss and increase the chances of survival. The objective of this research is to determine the optimal location of the automated external defibrillator in Muang Prachinburi district, which located in eastern part of Thailand. There are severe conditions which can be developed to sudden cardiac arrest such as severe trauma, acute cardiac arrest, respiratory disease and stroke. The maximal covering location problem (MCLP) is applied to find the location of electrical defibrillators based on the dispersion of incidences in need of urgent assistance in 2017. For disease distribution, top most incidences were in Na Mueng, Ban Phra and Dongkeelek sub districts. The largest increase in the number of diseases from 2015 to 2017 include strokes and heart attack account for approximately 27.75% and 24.26%, respectively. The number of emergency critical cases increase spreading to the center of urban area.  From the result, the maximal coverage with 40 AEDs within 2 km. is approximately 90.09% of coverage.