The long-baseline neutrino oscillation experiments depend on detailed models of neutrino interactions on nuclei. However, these models constitute an important source of systematic uncertainty partly due to the missing final state neutrons in current detectors. As such, neutron detection and reconstruction is desired in the near detectors of future long-baseline neutrino experiments. A 3D projection scintillator tracker known as the Super-FGD will be used as the upgrade for the off-axis near detector of T2K. Due to the good timing resolution and fine granularity, this technology is capable of measuring neutron kinetic energy from neutrino interactions and can provide valuable data for refining neutrino interaction models and better reconstruct the neutrino energy. Neutron beam data has been taken in Los Alamos National Lab (LANL) in both 2019 and 2020 with neutron energy ranging from 0 to 800 MeV using two prototypes of such a detector. In order to demonstrate the capability of the neutron detection, a total neutron-scintillator cross section on C-H is measured with one of the prototypes. In this poster, the details of the cross section measurement and the associated systematic uncertainties will be presented.