This　paper　addresses　a　robust　optimal　damping　control　for　the　grid-forming　converters.　The　proposed　control　strategy　calculates　the　optimal　damping　and　inertia　parameters　in　form　of　constant　gains　via　an　H∞-based　static　output　feedback　control　synthesis.　The　capability　and　effectiveness　of　the　proposed　control　methodology　are　proved　by　theoretical　analysis,　simulation,　and　experimental　results　on　a　typical　grid-connected　converter.　It　is　shown　that　the　designed　controller　can　guarantee　the　robust　performance　and　improves　system　stability.　The　simplicity　of　control　structure,　and　providing　desirable　inertia　and　damping　characteristics　in　a　software　program　can　be　considered　as　the　main　advantages　of　the　proposed　methodology.　©　2021　IEEE.