We construct a q-deformation of the plane wave as a formal power serie
s in the noncommutative coordinates of q-Minkowski space-time and four
-momenta. This q-plane wave has analogous properties to the classical
one, in particular, it has the properties of q-Lorentz covariance, and
it satisfies the q-d'Alembert equation (proposed earlier by one of us
) on the q-Lorentz covariant momentum cone. On the other hand, this q-
plane wave is not an exponent or q-exponent. Thus, it differs conceptu
ally from the classical plane wave and may serve as a its regularizati
on. We also give the polynomial solutions of the q-d'Alembert equation
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