  With the grand desert hypothesis, we have proposed to probe the
supersymmetric Grand Unified Theories (GUTs) at the future proton-proton (pp)
colliders and Hyper-Kamiokande experiment previously. In this paper, we study
the supersymmetric GUTs with gravity mediated supersymmetry breaking in
details. First, considering the dimension-six proton decay via heavy gauge
boson exchange, we point out that we can probe the supersymmetric GUTs with GUT
scale $M_{GUT}$ up to $1.778\times 10^{16}$ GeV at the Hyper-Kamiokande
experiment. Second, for the supersymmetric GUTs with $M_{GUT} \ge 1.0\times
10^{16}$ GeV and $M_{GUT} \ge 1.2\times 10^{16}$ GeV, we show that the upper
bounds on the universal gaugino mass are $7.2$ TeV and 3.5 TeV, respectively,
and thus the corresponding upper bounds on gluino mass are 15 TeV and 8 TeV,
respectively. Also, we shall study the masses for charginos, neutralinos,
squarks, sleptons, and Higgs particles in details. In particular, the
supersymmetric GUTs with $M_{GUT} \leq 1.2\times 10^{16}$ GeV can be probed at
the Hyper-Kamiokande experiment, and the supersymmetric GUTs with $M_{GUT}\ge
1.2\times 10^{16}$ GeV can be probed at the future 100 TeV pp collider
experiments such as the ${\rm FCC}_{\rm hh}$ and SppC via gluino searches.
Thus, the supersymmetric GUTs with gravity mediation can be probed by the ${\rm
FCC}_{\rm hh}$, SppC, and Hyper-Kamiokande experiments. In our previous study,
we have shown that the supersymmetric GUTs with anomaly and gauge mediated
supersymmetry breakings are well within the reaches of these experiments.
Therefore, our proposal provides the concrete scientific goal for the ${\rm
FCC}_{\rm hh}$, SppC, and Hyper-Kamiokande experiments: probing the
supersymmetric GUTs.
