  We show that the uniform radius of spatial analyticity $\sigma(t)$ of
solution at time $t$ for the fifth order KdV-BBM equation cannot decay faster
than $1/t$ for large $t>0$, given initial data that is analytic with fixed
radius $\sigma_0$. This significantly improves a recent result by Carvajal and
Panthee, where they established an exponential decay of $\sigma(t)$ for large
$t$.
