  Measurement of the self coupling of 125 GeV Higgs boson is one of the most
crucial tasks for high luminosity run of the LHC and it can only be measured in
the di-Higgs final state. In the minimal supersymmetric standard model, heavy
CP even Higgs ($H$) can decay into lighter 125 GeV Higgs boson ($h$) and
therefore influence the di-Higgs production. We investigate the role of single
$H$ production in the measurement of self coupling of $h$. We find that $H
\rightarrow hh$ decay can nontrivially affect the $h$ self coupling measurement
in low tan$\beta$ regime when the mass of the heavy Higgs boson lies between
250 - 600 GeV and depending on the parameter space it may be seen as an
enhancement of the self coupling of 125 GeV Higgs boson.
