This paper attempts to evaluate the productive efficiency of Keelung Port container terminals by using Data Envelopment Analysis (DEA) technique. The causes and extent of inefficiency for input factors and output combinations are explained via efficiency analysis, slack analysis, and sensitivity analysis. The results indicate that terminal No.3 has the highest average efficiency (0.9529), followed by terminal No. 1 (0.9243). Terminal No. 2 has the lowest average efficiency (0.8171) due mainly to insufficient yard handling activities. The results also show that energy consumption, quay cranes, and yard machines are the major factors responsible for productive inefficiency. To improve the container handling efficiency, we suggest that Keelung Port Authority enhance the maintenance of container equipment, sell or rent yard equipment to the yard leaseholder for terminal No. 2, relocate the Ship & Machinery Works between terminals No. 1 & No. 3 so that both yards can share the equipment and stevedores. Finally, privatization of terminal operations by encouraging stevedores to form a container handling company seems a promising direction in enhancing the productive efficiency.