In order to analyse the epitaxial growth by metalorganic chemical vapour deposition (MOCVD) of mercury telluride, HgTe, a 2D numerical model has been developed to simulate the gas flow in a horizontal MOCVD reactor. This model takes into account the Navier-Stokes equations coupled with the heat transfer and mass transport of chemical species. For the mathematical resolution of the governing equations a commercial solver, which can be run in a conventional personal computer, has been used. The study carried out presents a discussion about the dominant growth regime in a MOCVD growth as a function of different parameters: substrate temperature, total flow, partial pressure of precursors and reactor pressure. Emphasis is made on the fact that the substrate temperature is not the only parameter, which determines the growth regime. The use of two inlets, one for the Te precursor and the other for the mercury has been analysed in the framework of the numerical simulation. (C) 2002 Elsevier Science B.V. All rights reserved.