We have used a polarized spatially resolved microluminescence technique to investigate photocarrier charge and spin transport at 6 K in a GaAs nanowire (NW; n-type doping level ≈10 17 cm −3). Because of the difference in expansion coefficients of the NW and of its SiO 2 substrate, the NW is under strain, as revealed by the splitting between light-and heavy-hole emissions in the luminescence intensity spectrum. Light valence levels lie above the heavy valence ones, which is attributed as being caused by a tensile strain along both the axial and the lateral directions of the NW, equivalent to a compressive strain in the direction of light excitation. The symmetry group of the perturbed nanowire is then lowered to C 2v. No spin polarization can be evidenced for the heavy valence levels. The electron spin polarization decays up to a distance of 5 µm from the excitation spot, because of spin relaxation, and stays constant for larger distances because of the increased value of the drift velocity. Remarkably, the light-hole spin polarization exhibits damped spatial oscillations over as much as 5 µm. Analysis of the effect of strain on valence states shows that these oscillations are caused by the spin-orbit interaction in the light valence level. It is found that, for the C 2v point group, the corresponding Hamiltonian is linear in momentum. This spin-orbit interaction causes coherent oscillations rather than a spin relaxation process since transport essentially has a drift character in the internal electric field. The equivalent effective magnetic field induced by spin-orbit interaction and strain is, taking a light-hole g factor of 1, of the order of 60 mT.