In this work, we present some existence theorems of weighted pseudo almost periodic solutions for N-th order neutral differential equations with piecewise constant argument by means of weighted pseudo almost periodic solutions of relevant difference equations.
We present some conditions for the existence and uniqueness of almost automorphic solutions of third order neutral delay-differential equations with piecewise constant of the form（X（t） ＋px（t - 1））″′, = a0x（[t]） ＋ a1x（[t - 1]） ＋ f（t）,where [.] is the greatest integer function, p, a0 and al are nonzero constants, and f（t） is almost automorphic.
