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]) + a_1x([t-1]) + f(t),where [·] is the greatest integer function,p,a0 and a1are nonzero constants,and f(t) is almost automorphic.