Volcanic gas CO2/SO2 ratios in the plume of Stromboli Volcano (2006-2012 period), acquired using a Multi-GAS of the Istituto Nazionale di Geofisica e Vulcanologia - Sezione di Palermo monitoring network. Data are reported for the bulk plume released by the summit crater. All ratios are expressed on molar basis. Note that this file includes only processed data showing ratios of gases (calculated using the Ratiocalc software).The reported CO2/SO2 ratios are daily averages. The CO2 flux was calculated from combination of CO2/SO2 ratios and daily averaged SO2 fluxes, measured by the FLux Automatic MEasurement (FLAME) scanning DOAS (Differential Optical Absorption Spectroscopy) network of Istituto Nazionale di Geofisica e Vulcanologia - Osservatorio Etneo.