  We construct quantum supersymmetric pairs $({\bold U},{\bold U}^\imath)$ of
type AIII and elucidate their fundamental properties. An $\imath$Schur duality
between the $\imath$quantum supergroup ${\bold U}^\imath$ and the Hecke algebra
of type B acting on a tensor space is established, providing a super
generalization of the $\imath$Schur duality of type AIII. Additionally, we
construct a (quasi) $K$-matrix for arbitrary parameters, which facilitates the
realization of the Hecke algebra action on the tensor space.
