Data were collected on olivine hosted melt inclusions from four Icelandic eruptions: Stapafell, Haleyjabunga, Berserkjahraun and Heilagsdalsfjall. These data were released as part of the paper "The global melt inclusion C/Ba array: Mantle variability, melting process, or degassing?", published in Geochimica et Cosmochimica Acta, with doi: 10.1016/j.gca.2020.09.030. The data collected to place new constraints on the volatile content of the Icelandic mantle source. The data include measurement of C and H by Secondary Ion Mass Spectrometry, lithophile trace elements (including Ba and Nb) by Secondary Ion Mass Spectrometry, and measurement of major element composition of the melt inclusions and their olivine hosts by Electron Probe Microanalysis. The data were collected in 2017-2018, between Edinburgh (NERC ion probe facility) and Cambridge (EPMA).