A fuel injector for spraying fuel into a combustion chamber comprises a spray head (6) extending along a central axis (X) from a base (6a) to a free end (6b), the head comprising a free outside face (6c, 6d) defining an internal injection combustion (6), and at least two groups (01; 20; 30) of injection orifices, each of the groups (10; 20; 30) of injection orifices comprising a first orifice (11; 21; 31) and at least one second orifice (12; 22; 32), each adapted to spray a fuel jet along a respective first and second directions (D11, D21, D31; D12, D22, D32), the first and second directions forming between them an acute angle (.alpha.). All of the internal openings of the injection orifices in each of the groups of orifices are situated substantially in a common plane (P) extending substantially transversely relative to the central axis (X) of the head (6) of the injector. The injector particularly intended for a direct-injection diesel engine.