The coherent combination of multi-Hermite-Gaussian beams is proposed to describe the flat-topped beams. Based on the Wigner distribution function and intensity moments methods, the analytical equations of beam propagation factor (M 2 factor) and kurtosis parameter (K parameter) of the resulting beam are derived in the general case. It is shown that a flat-topped intensity profile of the resulting beam can be obtained at a certain plane by an appropriate choice of the parameters of Hermite-Gaussian beams. Numerical examples are given to illustrate properties of the resulting beam.