Hot Isostatic Pressing (HIP) is a well known technique for the production of metal matrix composites. However, little attention has been given to the factors which influence the densification of these materials in actual processing conditions. In the present work the densification process was studied in an iron-based composite reinforced with fine TiC particles. The results revealed that the presence of a high amount of rigid-rigid contacts and the formation of ceramic particle networks within the composite powder mixture increase the pressure required for densification. The fine matrix particles were found to contribute more effectively to the densification of the composite than the coarse particles do.