  The paper introduces the class of split regular BiHom-Poisson superalgebras,
which is a natural generalization of split regular Hom-Poisson algebras and
split regular BiHom-Lie superalgebras. By developing techniques of connections
of roots for this kind of algebras, we show that such a split regular
BiHom-Poisson superalgebras $A$ is of the form $A=U+\sum_{\a}I_\a$ with $U$ a
subspace of a maximal abelian subalgebra $H$ and any $I_{\a}$, a well described
ideal of $A$, satisfying $[I_\a, I_\b]+I_\a I_\b = 0$ if $[\a]\neq [\b]$. Under
certain conditions, in the case of $A$ being of maximal length, the simplicity
of the algebra is characterized.
