In this research a cell stack with standard power output of 100 [W] was tested over a period of 3700 h. After the long-term operation a subsequent post-test analysis of the anode microstructure was conducted using a combination of focused ion beam and scanning electron microscopy. Obtained data was reconstructed into three-dimensional images, based on which the microstructure parameters were obtained. The microstructure parameters were quantified at three different locations in the selected cell; the inlet, the middle and the outlet. This is the first paper in the open literature, known to the authors, that uses the three dimensional microstructure reconstruction technique to evaluate the local evolution of a SOFC anode's microstructure. The obtained results indicate strong non-homogeneous microstructure morphology changes after long-term operation. (c) 2015 Elsevier B.V. All rights reserved.