Generation of ultrashort vortex pulses by spiral array

•We put forward an approach for flexible selection of orbital-angular-momentum mode in the ultrashort laser pulse by an optical mask of the spiral array.•To our knowledge, this is the first time systematically and theoretically studying the formation of the ultrashort orbital-angular-momentum pulses by the optical mask diffraction.•We experimentally performed the function of the optical spiral array selecting the orbitalangular-momentum modes in ultrashort pulses, and the experimental results are highly consistent with the theoretical analyses.•The optical mask has the advantages of damage-resistance, without medium-dispersion, and ease of handling in ultrafast optics.•The spiral array is available to apply for the analysis and generation of other matter vortex beams within an axially scalar system.