Nano-structured composite electrode with carefully conducted infiltration process is one of the most promising electrode structure of intermediate temperature solid oxide fuel cells (IT-SOFCs) due to its promoted oxygen reduction reaction (ORR) and enlarged triple phase boundaries (TPBs). In here, we demonstrate the rational design of infiltrated nano-structures with enhanced ORR kinetics and an excellent stability for IT-SOFCs. We systematically designed the nano-structured cathode functional layer (CFL) with the infiltration of Sm0.5Sr0.5CoO3-δ (SSC) into the porous Gd0.2Ce0.8O2-δ (GDC). By controlling the drying process during infiltration process, two distinct nano-structures of SSC, discrete coating and film-like coating, were fabricated on the GDC scaffolds. The CFL with film-like coating showed ~30 % reduction in Rp and ~15 % increase in peak power density at 650 °C compared to the CFL with discrete coating in spite of ~12 fold less loading of infiltration materials. Furthermore, the CFL with film-like coating showed an excellent stability, maintaining Rp of 0.029 Ωcm2 for 100 h at 650 °C. Our results demonstrated that the high performance and stability of composite electrodes for IT-SOFCs can be achieved through the thin-film coated CFL.