Abstract: Mobile robot for obstacle avoidance is a simple machine with collision avoidance. In addition, it has very big to exploration in future development. By using this simple collision avoidance system, a lot of diversity and new mobile robot which have different functions is invented. The avoidance of obstacle in real time is consider as a one of key issues to success the mobile robot application systems. In this study mobile robot with a voiding the collision is developed by using onboard sensors and the microcontroller. The designed robot is capable of moving in an environment which has obstacles with avoiding the collisions. It is a robot platform which has a four wheels and an ultrasonic range sensor that is fixed in the front of it for scanning the environment. The ultrasonic range sensor will feedback a triggered signal to the microcontroller wirelessly using Bluetooth that programmed in Arduino IDE.