  Neutron-induced nuclear recoil background is critical to the dark matter
searches in the PandaX-4T liquid xenon experiment. This paper studies the
feature of neutron background in liquid xenon and evaluates their contribution
in the single scattering nuclear recoil events through three methods. The first
method is fully Monte Carlo simulation based. The last two are data-driven
methods that also use the multiple scattering signals and high energy signals
in the data, respectively. In the PandaX-4T commissioning data with an exposure
of 0.63 tonne-year, all these methods give a consistent result that there are
$1.15\pm0.57$ neutron-induced background in dark matter signal region within an
approximated nuclear recoil energy window between 5 and 100 keV.
