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Cosmological perturbations in the (1+3+6)-dimensional space-times includingphoton gas without viscous processes are studied on the basis of Abbott etal.'s formalism. Space-times consist of the outer space (the 3-dimensionalexpanding section) and the inner space (the 6-dimensional section). The innerspace expands initially and contracts later. Abbott et al. derived onlypower-type solutions in the small wave-number limit which appear at the finalstage of the space-times. In this paper, we derive not only small wave-numbersolutions, but also large wave-number solutions. It is found that the lattersolutions depend on the two wave-numbers k_r and k_R (which are defined in theouter and inner spaces, respectively), and that the k_r-dependent andk_R-dependent parts dominate the total perturbations when (k_r/r(t))/(k_R/R(t))>> 1 or << 1, respectively, where r(t) and R(t) are the scale-factors in theouter and inner spaces. By comparing the behaviors of these perturbations,moreover, changes in the spectrum of perturbations in the outer space with timeare discussed.