  Using lattice QCD simulation in the quenched approximation, we study the
$\kappa$ meson, which is ^3P_0 in the quark model, and compare experimental and
other lattice data. The $\kappa$ is the lowest scalar meson with strangeness
and constitutes the scalar nonet. The obtained mass is much higher than the
recent experimental value, and therefore the $\kappa(800)$ is difficult to
consider as a simple two-body constituent-quark structure, and may have another
unconventional structure.
