The IUE observatory and the UVS instrument on board the Voyager spacecraft have measured EUV Jovian auroral emission and given evidence for its strong longitudinal dependence. However, limited spatial resolution has not allowed the derivation of any information concerning the latitudinal structure, nor even the exact location of the excitation process. This study is an attempt to relate the atmospheric auroral features to the magnetospheric mechanisms which generate the auroral precipitation of particles and, if possible, to allow the identification of the particle species, energy, L shell of injection, and equatorial anisotropy. Under assumptions consistent with a “diffuse” auroral process, we have estimated the precipitated flux for particles drifting in the distorted Jovian magnetic field, and we have shown that the effect of the magnetic field asymmetry by itself is able to account for the main longitudinal features of the observed emissions through the loss cone variations. We have then analyzed the dependence of the predicted precipitation profiles in both hemispheres on the model parameters, namely the L shell value and the anisotropy of the source. By comparison with the observations, we derive that the bulk of the emissions, almost longitude‐independent, is due to quasi‐isotropic equatorial distributions in the loss cone, depends only slightly on the L shell parameter, and does not depend on the particle species. This implies that the auroral brightness observations cannot by themselves provide enough information on this main component of the magnetospheric losses (beyond its equatorial angular distribution). Conversely, the brightness peaks observed near λIII = 180° in the northern hemisphere and λIII = 0° in the southern one, which are shown to originate from particles with anisotropic angular distributions, very clearly depend on all the model parameters. That is to say that because of the peculiar Jovian magnetic field structure, these rather moderate contributions to the auroral emissions (10 to 25% each) are closely related to the auroral injection mechanisms. Finally, using both brightness profiles from the Voyager observations and recently published EUV color ratios from IUE, we have obtained one possible scenario of the magnetospheric losses into the Jovian atmosphere involving different particle species of different energy injected on various L shells of the middle magnetosphere. In particular the northern peak is interpreted as due to electrons (or perhaps protons depending on the plasma lag to rigid corotation) while the southern peak is attributed to ions. New constraints on the surface magnetic field strength (namely the location of its minima) are also derived which could help to reduce the uncertainties in the higher multipole terms of the magnetic field model.