  In this paper, we prove generalized Hyres--Ulam--Rassias stability of the
mixed type additive, quadratic and cubic functional equation
$$f(x+ky)+f(x-ky)=k^2f(x+y)+k^2f(x-y)+2(1-k^2)f(x)$$ for fixed integers $k$
with $k\neq0,\pm1$ in non-Archimedean spaces.
