  The determination of the uncertainty measures of multidimensional quantum
systems is a relevant issue \textit{per se} and because these measures, which
are functionals of the single-particle probability density of the systems,
describe numerous fundamental and experimentally accessible physical
quantities. However, it is a formidable task (not yet solved, except possibly
for the ground and a few lowest-lying energetic states) even for the small
bunch of elementary quantum potentials which are used to approximate the
mean-field potential of the physical systems. Recently, the dominant term of
the Heisenberg and R\'enyi measures of the multidimensional harmonic system
(i.e., a particle moving under the action of a $D$-dimensional quadratic
potential, $D > 1$) has been analytically calculated in the high-energy (i.e.,
Rydberg) and the high-dimensional (i.e., pseudoclassical) limits. In this work
we determine the exact values of the R\'enyi uncertainty measures of the
$D$-dimensional harmonic system for all ground and excited quantum states
directly in terms of $D$, the potential strength and the hyperquantum numbers.
