The valve ignition prechamber (1) with a reversed direction of combustion includes a lamination cavity (6) in which opens a pilot charge injector (32), and said cavity (6) being connected to a combustion chamber (5) of an internal combustion engine by a lamination duct (7), which, when opened by a lamination valve (13), forms with the latter a torch-ignition prechamber while an inverter housing (93) containing an ignition pilot charge (27) and accommodating ignition means (11) is housed in the lamination cavity (6) with which it forms a late combustion volume, said housing (93) comprising a main ejection nozzle (94) which can emit a pre-ignition torch in the direction of the lamination duct (7), the volume swept by said torch forming an early combustion volume.