This dataset includes results from glass major- and trace-element compositions of the last four explosive silicic eruptions from Ilopango caldera in El Salvador (TBJ, TB2, TB3, and TB4). Major elements in the glass shards were analyzed employing a JEOL JXA 8200 wavelength dispersive microprobe at the GEOMAR - Helmholtz-Centre for Ocean Research Kiel, whereas trace-elements were determined by Laser Ablation Inductively Coupled Plasma - Mass Spectrometry (LA-ICP-MS) at Institute of Earth Sciences, Academia Sinica in Taipei (Taiwan).