This study incorporated the authors' previously published micro heat exchanger with a newly designed micro pump to develop a high-performance, mini size liquid cooling system. An integrated pump and cold-plate assembly was also developed for further reducing the overall size of the system. The test results show that the micro pump provides a higher maximum pressure head and maximum flow rate in comparing to the performance of the commercial products. The performance of the entire liquid cooling system is similar to that of the recently announced product. The present study shows an optimum combination of a slim cold plate and a high-pressure-head micro pump. It provides a comparable thermal resistance but much smaller size and therefore lower cost than most of the commercial liquid cooling systems.