Operator splitting is a widely used procedure in the numerical solution of initial and boundary value problems of partial differential equations. In this paper the error of the operator splitting, the so-called splitting error, is investigated. The mathematical background of operator splitting is shortly discussed. Sufficient conditions, under which the splittingerror vanishes, are formulated for the splittingmetho d of the Danish Eulerian Model. The study is based on the L-commutativity of the operators used in the model. Finally, the size of the splitting error is analysed in the case where the splitted operators are linear.