This paper seeks to explain how Banda Aceh and Higashimatsushima how they made recovery after natural disasters. Both cities experienced the same natural disasters namely the earthquake and tsunami. Although in different periods of time, Banda Aceh in 2004 and Higashimatsushima in 2011. As a result of these natural disasters Banda Aceh and Higashimatsushima suffered severe damage, many people lost their homes and other property. JICA created a program for joint reconstruction of Banda Aceh and Higashimatsushima in infrastructure recovery, because the two cities have many similarities in terms of territory and society. The program created by JICA is called "Community Based Mutual Reconstruction Acceleration Program by Utilization of Local Resources in Banda Aceh and Higashimatsushima (CoMU Project)". This paper focuses on what efforts have been made by JICA to carry out reconstruction with Banda Aceh and Higashimatsushima and how the CoMU Project was implemented in the post-disaster recovery process. This paper uses Rational Choice Institutionalism to explain what benefits are obtained from both cities and how the two cities help each other for the recovery process. The success of CoMU Project has made the two cities able to deal with post-natural disaster problems, both cities have succeeded in increasing their economies by cultivating marine products, and both cities have also carried out disaster mitigation efforts to prevent natural disasters