A dedicated Implantable Intrathecal pump system has been developed to control dug infusion. The system consist of a motor, two batterries, a controller and a reservoir including drug. We developed a small-sized controller (22*36*11mm) which is implantable, programmable and without any wire out of the case. The Controller have functions: 1)motor control 2)Data communication and 3) system monitoring. A software has been developed in order to minimize power consumption and control the infusion mode. Generally, the system including CPU and modules has been in Sleep Mode and execute infusion or communication when internal or external interrupt is occurred. There are four infusion mode(simple continuous, single bolus, periodic bolus and complex) for individual patient. The communication based on RS232 is used for data reception to control the system and for data transmission to monitor the system with external GUI. Using the system, We have implemented and tested the functions. We found out the best performance of the system and tested the controllability of software and energy efficiency. In our results, the system has improved than the previous system. And favorable results were achieved in the drug infusion control with wireless communication using the bluetooth module.