The orientation of acicular Fe particles in magnetic coating media was investigated by the use of a polarized light reflection technique. The particle volume fraction, φ_P, of the magnetic coatings was changed from 30.5 to 53.7 vol%. The reflection ratio was compared with the squareness of the hysteresis for the coatings, measured by VSM, indicating the maximum value when plotted as a function of φ_P. The reflection intensity was strongly influenced by the surface roughness of the magnetic coatings. At a value of φ_P=45.1 vol%, the particles were well dispersed in the media, with the result that the coating surface became very smooth. The orientation of particles in a magnetic paint was also expressed as a function of the angle between the electric vector of the polarized light and the direction of the applied magnetic field. However, the reflection ratio as a function of another volume fraction, φ_PL, of the magnetic paints decreased with an increase in the apparent viscosity of the magnetic dispersion.