  In this paper, we study the single top production in association with a Higgs
boson in the $U(1)_{B-L}$ extension of the Standard Model at the LHC. We
calculate the production cross sections of the processes $pp\rightarrow
thX(h=H_{1},H_{2};X=j,b,W)$ in this model. Then we further study the
observability of the process $pp\rightarrow tH_{2}j$ through $pp\rightarrow
t(\rightarrow q\bar{q'} b)H_{2}(\rightarrow 4\ell)j$. We find that the
systematic significance can be improved obviously, but it is still challenging
for the 14 TeV LHC with high-luminosity to detect this signal.
