Lymphopoiesis is the generation of the T, B and NK cell lineages from a common lymphoid-biased haematopoietic stem cell. The experimental study of this process has generated a large amount of cellular and molecular data. As a result, there is a considerable number of mathematical and computational models regarding different aspects of lymphopoiesis. We hereby present a regulatory network consisting of 95 nodes and 202 regulatory interactions among them. The network is studied as a qualitative dynamical system, which has as stationary states the molecular patterns reported for CLP, pre-B, B naive, PC, pNK, iNK, NK, DP, CD8 naive, CTL, CD4 naive, Th1, Th2, Th17 and Treg cells. Also, we show that the system is able to respond to specific stimuli to reproduce the ontogeny of the T, B and NK cell lineages.