We　present　a　method　of　single-frame　reconstruction　in　off-axis　digital　holography　with　Kronecker-product　interpolation　to　maximize　spatial-frequency　extraction.　The　Kronecker-product　interpolation　operated　on　a　one-frame　off-axis　digital　hologram　can　generate　several　aliasing　spectra　in　its　Fourier　domain,　where　the　zero-order　aliasing　spectra　in　the　extrapolation　region　can　be　suppressed　effectively.　After　adding　all　aliasing　spectrum　regions　and　substituting　each　aliasing　spectrum　in　place　with　their　sum,　spectrum　interception　with　a　larger　scope　for　filtering　can　be　made　in　one　of　the　aliasing　spectrum　regions.　The　experimental　results　demonstrate　that　the　method　is　valid　to　improve　the　resolution　in　off-axis　digital　holography.　(C)　2020　Optical　Society　of　America