  We investigate the boson star with the self-interacting scalar field as a
model of galactic halos. The model has slightly increasing rotation curves and
allows wider ranges of the mass($m$) and coupling($\lambda$) of the halo dark
matter particle than the non-interacting model previously
suggested(ref.\cite{sin1}). Two quantities are related by
$\lambda^{\frac{1}{2}} (m_p/m)^2\st{>}{\sim} 10^{50}$.
