A new parallel version of the Danish Eulerian model for long transport of air pollutants over the territory of Europe (UNI–DEM) is presented. It is based on the domain partitioning of the space domain both in the
directions. This new approach gives possibilities to use large number of processors (or cores) on the IBM BlueGene/P computer. The new version of the parallel code of the UNI–DEM is created by using MPI standard library and appears to be highly portable and shows good efficiency and scalability. Discussions according to the performance, speed-ups and efficiency achieved in the first testing runs of the new parallel code on an IBM Blue Gene/P computer are presented.