  We investigate the influence of the universal extra dimension on the
branching ratio in the $B \to \pi(\rho) \ell^+ \ell^-$ decay. Taking $1/R\sim
\{200-1000\}$GeV with one universal extra spatial dimension, which is
consistent with the experimental data for ${\cal B}(B \to X_s \gamma) $, ${\cal
B}(B \to K^\ast \mu^+\mu^- $) and the electroweak precision tests, we obtain
that for both ($\mu,\tau$) channels the branching ratio strongly depends on the
compactification radius 1/R.
