The only freshwater pesut owned by Indonesia is the Pesut-Mahakam, or its Latin name Orcaella brevirotis. The pesut-Mahakam belongs to the category of critically endangered and endangered animals. This study aims to produce an application with an increase in reality that can socialize and educate about Pesut-Mahakam, an Android-based company. Software development process model for Rapid Application Development. Software testing is done through Marker Test and System Functionality Test. The test results show that the Augmented Reality 3D Pesut-Mahakam application is feasible and able to socialize and provide education as expected.