The present work reports on the charge and spin density modelling of YTiO$\sb 3$ in its ferromagnetic state (T$\sb C$ = 27K). Accurate polarized neutron diffraction and high-resolution X-ray diffraction (XRD) experiments were carried out on a single crystal at the ORPHÉE reactor (LLB) and SPRING8 synchrotron source. The experimental data are modelled by the spin resolved pseudo-atomic multipolar model (Deutsch et al., 2012). The refinement strategy is discussed and the result of this electron density modelling is compared with that from XRD measured at 100K and with density functional theory calculations. The results show that the spin and charge densities around the Ti atom have lobes directed away from the O atoms, confirming the filling of the t$\sb 2g$ orbitals of the Ti atom. The d$\sb xy$ orbital is less populated than d$\sb xz$ and d$\sb yz$, which is a sign of a partial lift of degeneracy of the t$\sb 2g$ orbitals. This study confirms the orbital ordering at low temperature (20K), which is already present in the paramagnetic state above the ferromagnetic transition (100K).