  We study the ground state of the boundary Izergin-Korepin model. The boundary
Izergin-Korepin model is defined by so-called $R$-matrix and $K$-matrix for
$U_q(A_2^{(2)})$ which satisfy Yang-Baxter equation and boundary Yang-Baxter
equation respectively. The ground state associated with identity $K$-matrix
$K(z)=id$ was constructed in earlier study [Yang and Zhang,
Nucl.Phys.B596,495-(2001)]. We construct the free field realization of the
ground state associated with nontrivial diagonal $K$-matrix.
