Let $\overline{L}$ be a metrized line bundle on an analytic space $\mathrm{X}$ and let $\mathrm{U}$ be an open subset of $\mathrm{X}$. One says that $\overline{L}$ is strongly pluriharmonic on $\mathrm{U}$ if for any local frame $s$ of $L$ defined on an open subset $\mathrm{V}\subset\mathrm{U}$, $\log\left\|{s}\right\|^{-1}$ is strongly pluriharmonic on $\mathrm{V}$.