Abstract: A process is described for catalytic cracking of a petroleum feed in which a catalyst from a regeneration zone 4 is caused to flow in a dense fluidized bed conditioning zone 2 upstream of an injection zone 10, the fluidization rate being 0.1 to 30 cm/s. The throughput of catalyst into injection zone 10 is regulated by a constriction means 11. The hydrocarbon feed 12 is injected below the constriction means and flows counter-current to the direction of flow of the shaped catalyst flow. The hydrocarbon feed 12 is injected at a set injection angle depending on the movement of the feed and the catalyst.