As an index of molding, the fractal dimension of pores can reflect system varying details as the density. Pores in the powder aggregates with a composition of Fe-2%Cu-0.5%C were researched. The change tendency of dimension of pores as a function of compaction pressure or sintering temperature was investigated. Result indicates that the dimensions of pores in this ternary system decrease both in the process of compacting and sintering. It is convenient to build up some theories by combining compacting and sintering based on the variation of pore dimensions. (c) 2010 The Society of Powder Technology Japan. Published by Elsevier B.V. and The Society of Powder Technology Japan. All rights reserved.