  Measuring the triple Higgs coupling is a crucial task in the LHC and future
collider experiments. We apply the Message Passing Neural Network (MPNN) to the
study of the non-resonant Higgs pair production process $pp \to hh$ in the
final state with $2b + 2\ell + E_{\rm T}^{\rm miss}$ at the LHC. Although the
MPNN can improve the signal significance, it is still challenging to observe
such a process at the LHC. We find that a $2\sigma$ upper bound (including a
10\% systematic uncertainty) on the production cross section of the Higgs pair
is 3.7 times the predicted SM cross section at the LHC with the luminosity of
3000 fb$^{-1}$, which will limit the triple Higgs coupling to the range of
$[-3,11.5]$.
