Sensors are fundamental to all health monitoring systems. As technology advances in fields such as nanotechnology and MEMS (Microelectromechanical Systems), wearable sensors to be used in these systems are not bulky anymore. Since their quality increases, health monitoring systems are implemented in various scenarios. Underwater applications can be given as an example to these scenarios. When it comes to underwater electronic devices, one of the most frequently used equipment by divers is diving computer. Basically, the purpose of the equipment is to calculate gas loads of tissues through mathematical models of tables; and to guide divers based on these calculations and to provide information for future diving activities. They cannot be modified to collect physiological data from divers such as body temperature and muscle movement. In this work, a development board to collect physiological data from divers that can be introduced to the users is designed. This board aims to bring together all hardware and software required to monitor underwater physiological attributes of divers. This study includes developed kit's design stages and its functions.