Background: Since 2004, the number of installed Automated External Defibrillator (AED) has been increased in Japan annually, the cumulative number of sold AED more than 600,000 units by 2016. Despite there have been about 130,000 out of hospital cardiac arrest annually, there have only 1302 cases delivered defibrillation by bystanders at the scene. Therefore, we investigate that number of AED installation and usage rate for Out of Hospital Cardiac Arrest (OHCA) patients. Methods: Retrospective metropolitan wide cohort study. Subject: Total 13,364 OHCA patients in the Tokyo Metropolitan area from Jan. 1 through Dec. 31 in 2012 were eligible for theses analyses. Also, OHCA occurrence place and AED usage rate were studied. Results: 82.8% of OHCA occurred at residences, 10% at outdoors, 6.4% at indoors, only 0.7% at schools. In the other hand, highest bystander’s CPR rates were found in sports facilities and schools (71.4%). The installation rate of AEDs in residences was 9.6%, instead of highest incidence for OHCA patients, school and sports institute made up 21.4% of AED installations, but only 1.0% of the incidences of cardiac arrest. We found that there is a mismatch between incidence sites of cardiac arrest and locations of installed AED. Discussion: It is essential to increase the number of AED installations. Furthermore, it is desirable to install AEDs in locations where cardiac arrest is liable to occur following guidelines for the proper placement of AEDs, and important to further spread BLS education among the general citizens.