  We consider the fifth order Kadomtsev-Petviashvili I (KP-I) equation as
$\partial_tu+\alpha\partial_x^3u+\partial^5_xu+\partial_x^{-1}\partial_y^2u+uu_x=0,$
while $\alpha\in \mathbb{R}$. We introduce an interpolated energy space $E_s$
to consider the well-posedeness of the initial value problem (IVP) of the fifth
order KP-I equation. We obtain the local well-posedness of IVP of the fifth
order KP-I equation in $E_s$ for $0<s\leq1$. To obtain the local
well-posedness, we present a bilinear estimate in the Bourgain space in the
framework of the interpolated energy space. It crucially depends on the dyadic
decomposed Strichartz estimate, the fifth order dispersive smoothing effect and
maximal estimate.
  Key words: The fifth order KP-I equation, Bourgain space, Dyadic decomposed
Strichartz estimate, Dispersive smoothing effect, Maximal estimate.
