  We report the measurement of the branching fraction of the $B^0 \to K_S^0
\pi^0 \gamma$ decay in $e^+ e^- \to \Upsilon(4S) \to B \overline{B}$ data
recorded by the Belle II experiment at the SuperKEKB asymmetric-energy collider
and corresponding to 190 fb$^{-1}$ of integrated luminosity. The signal yield
is measured to be $121\pm 29\,\hbox{(stat.)}$, leading to the branching
fraction ${\cal B}\left(B^0 \to K_S^0 \pi^0 \gamma\right) = \left(7.3 \pm
1.8\,\hbox{(stat.)} \pm 1.0\,\hbox{(syst.)} \right)\times 10^{-6}$, which
agrees with the known value.
