  In this work, we study the radiative and strong decay of $S$-wave
$K\bar{K}_1(1400)$ molecular state within the effective Lagrangians approach
and find the relation between the $K\bar{K}_1(1400)$ molecular state and the
newly observed $\eta_1(1855)$ state by comparing with the BESIII observation.
The prediction indicates that the decay width can reach up to
$182.97^{+2.79}_{-3.50}$ MeV, which can be confronted with the experimental
data. If the $\eta_1(1855)$ could be $S$-wave $K\bar{K}_1(1400)$ molecular
state, the $K\bar{K}^{*}\pi$ three-body decay provides the dominant
contribution, not the $\eta\eta^{'}$ channel found in the experiment. In
addition, the partial width for $\eta_1(1855)\to\gamma{}\phi$ can reach up to
$17.95^{+0.21}_{-0.43}$ KeV. Those results can be measured in future
experiments and used to test the nature of the $\eta_1(1855)$.
