Both observational and theoretical studies suggest that the magnetic field plays an important role in the process of massive star and cluster formation. However, many open questions still remain, including the exact role of B-field at the different scales (from cloud to disk scales) and its importance compared to turbulence, feedback and self-gravity. Multi-scale studies of the morphology and strength of the magnetic field are thus crucial to properly unveil the role of the magnetic field in the formation of high-mass stars. In this talk, I will mainly focus on the multi-scale study of the magnetic field toward the high-mass star-forming region G31.41+0.31 carried out with both single-dish and interferometric observations of polarized dust emission. G31.41+0.31 is one of the most studied objects in polarized emission and the first high-mass star-forming core to show an hourglass-shaped magnetic field morphology. Finally, I will also present three on-going observational campaigns that will allow us to further constrain the role of the magnetic field in massive star formation and to construct a multi-scale magnetized path of massive star formation.