Certain thermal (Matsubara) Green functions are obtained for a "free" system of quantum-deformed harmonic oscillators. It is shown that the form of the single-particle Matsubara function is changed, with an explicit dependence on s=l(n) q appearing in a simple form and suggesting that quantum-deformed commutation rules intrinsically incorporate interactions even in the "free case". A two-particle Matsubara function gives no evidence of a bound state energy shift.