2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/177173In this paper, we use the type Ia supernovae data to constrain the holographic dark energy model proposed by Li. We also apply a cosmic age test to this analysis. We consider in this paper a spatially flat Friedmann-Robertson-Walker Universe with matter component and holographic dark energy component. The fit result shows that the case $c<1$ ($c=0.21$) is favored, which implies that the holographic dark energy behaves as a quintom-type dark energy. Furthermore, we also perform a joint analysis of SNe+CMB+LSS to this model; the result is well improved, and still upholds the quintom dark energy conclusion. The best fit results in our analysis are $c=0.81$, $Ω_m^0=0.28$, and $h=0.65$, which lead to the present equation of state of dark energy $w_0=-1.03$ and the deceleration/acceleration transition redshift $z_T=0.63$. Finally, an expected SNAP simulation using $Λ$CDM as a fiducial model is performed on this model, and the result shows that the holographic dark energy model takes on $c<1$ ($c=0.92$) even though the dark energy is indeed a cosmological constant.21 pages, 9 figures. v2: Typos corrected; References added; A joint analysis of SNe+CMB+LSS added, and 3 figures and some references added accordingly. v3: Typos corrected; to appear in Phys. Rev. DAstrophysicstext