  This paper investigates the existence of almost periodic traveling fronts for
Fisher-KPP lattice equations in one-dimensional almost periodic media. By the
Lyapunov exponent of the linearized operator near the unstable steady state, we
give sufficient condition of the existence of minimal speed of traveling
fronts. Furthermore, it is showed that almost periodic traveling fronts share
the same recurrence property as the structure of the media.
  As applications, we give some typical examples which have minimal speed, and
the proof of this depends on dynamical system approach to almost periodic
Schrodinger operator.
