A 5-cell solid oxide fuel cell (SOFC) stack with external manifold structure is assembled and has undergone a long-term test for nearly 3500h at a current of 60A at 750 °C. Cells used in the stack are anode supported cells with yttria-stabilized zirconia (YSZ) electrolytes, Ni/YSZ hydrogen electrodes and YSZ based composite cathode. The size of the cell is 15×15 cm (active area: 13×13cm). Ceramic-glass sealant is used in the stack to keep the gas tightness between cells, interconnects and manifolds. In the test, pure hydrogen is used as fuel. Due to device limitations, the stack only got a maximum output of 350W at 95A. During the long-term test, the stack shows a degradation of 1.8% per 1000h. The stack is still running and shows a good stability. The applicability of stack with an external manifold structure in planar intermediate temperature SOFC has been demonstrated.