A method for installing railway tracks onto ballast beds avoiding the need for installing any type of auxiliary track. The method comprises successive stages to be carried out after having located the sleepers onto the ballast bed, consisting of fixing and laying of a pair of rails from a mini train, for the transport of the rails with the fastening and traction of same up to their complete unloading, the operation being guided by means of a discharge wagon; supporting the rails on rollers for the longitudinal movement thereof; cutting, squaring and fixing the adjacent ends to the consecutive rails; raising the rail with the help of a crane, and removing the rollers; partial fastening of the track and placement of the rollers for the next cycle, and removing the tractor from the mini train, and the final fastening of the rails.