  Recently,problem of stability of H-atom has been reported in extra-finite
dimension,and found out that it is stable in extra-finite dimension of
size,$R\leq\frac{a_0}{4}$,where,$a_0$ is the Bohr radius.Assuming that,the
heavy flavoured mesons have also such stability controlled by the scale of
coupling constant,we obtain corresponding QCD Bohr radius and it is found to be
well within the present theoretical and experimental limit of higher
dimension.We then study its consequences in their masses using effective string
inspired potential model in higher dimension pursued by us.Within the
uncertainty of masses of known Heavy Flavoured mesons the allowed range of
extra dimension is $L\leq10^{-16}m$,which is well below the present theoretical
and experimental limit,and far above the Planck length
$\simeq1.5\times10^{-35}$ m.
