A model, based on the Van Wyk model, is developed to predict the compaction behaviour of stack sequence of dry fabric plies, and is used a set of 3 parameters (stiffness k, pressure sensitivity n and initial fibre ratio Vf0) with P = (k(Vf- Vf))n. The method originality is to construct the behaviour law of a complex stack sequence by the assembly of elementary behaviours. Elementary behaviours are identified using initial experimental compaction tests and are linked to the interaction of a fabric ply with its surrounding environment (another fabric ply or the surface of the compressive mould). This proposed modelling approach have been tested on various carbon, flax and carbon/flax hybrid stack sequence, and seems efficient to predict their compaction behaviour. Its validity is limited to the range of stack sequence of a reduced number of plies. With stack sequence made of numerous fabric plies, some new phenomena must be taken into account. In complement we proposed a method to decompose the compaction behavior curve into three stages (rigid body movement of the fabric plies, nesting of the plies, densification). This method is relevant to compare easily some compaction curves and to evaluate the internal strain state of a stack sequence.