A theoretical model is developed and a molecular dynamics simulation technique is applied for the description of ultrashort laser ablation of metals. The ablation of Al, Ni, and Fe using 0.1, 0.5 and 5 ps laser pulses at wavelengths of 248 and 800 nm is studied. The process is investigated at fluences up to 0.5 J/cm(2). The analysis based on the temporal evolution of the ablation, the temperature, and the pressure distributions into the material reveals that a thermo-mechanical mechanism (spallation) takes place near the threshold. However, phase explosion is found to be the dominant mechanism of material removal at fluences higher than several hundreds Of mJ/cm(2). The influence of the laser parameters (wavelength and pulse duration) is obtained and discussed. The ablation depth as a function of the laser fluence and the ablation threshold value are evaluated and compared with the experimental data available. Good agreement between the theory and experiments is observed. (c) 2005 Elsevier B. V. All rights reserved.