  In this paper, we study the possibility of determining the neutrino mass
ordering from the future supernova neutrino events at the DUNE and T2HK
detectors. We estimate the expected number of neutrino event rates from a
future supernova explosion assuming Garching flux model corresponding to
different processes that are responsible for detecting the supernova neutrinos
at these detectors. We present our results in the form of $\chi^2$, as a
function of supernova distance. For a systematic uncertainty of 5\% in
normalisation as well as energy calibration error, our results show that, the
neutrino mass ordering can be determined at $5 ~\sigma$ C.L. if the supernova
explosion occurs at a distance of 42.7 kpc for T2HK and at a distance of 15.2
kpc for DUNE. Our results also show that the sensitivity of DUNE and T2HK get
affected by the systematic uncertainties for the smaller supernova distances.
Further, we show that in both DUNE and T2HK, the sensitivity gets deteriorated
to some extent due to presence of energy smearing of the neutrino events. This
occurs because of the reconstruction of the neutrino energy from the
energy-momentum measurement of the outgoing leptons at the detector.
