Dataset associated with the publication "Hybridization of Fossil- and CO2-Based Routes for Ethylene Production using Renewable Energy" by Iasonas Ioannou, Sebastiano C. D'Angelo, Antonio J. Martín, Javier Pérez-Ramírez, and Gonzalo Guillén-Gosálbez, available at https://doi.org/10.1002/cssc.202001312. The dataset includes the numeric data associated with most of the scenarios described in the main manuscript and in the Supporting Information (SI), as well as the tables presented in the main manuscript and in the SI converted in a machine-readable format. The structure of the dataset is here elucidated sheet by sheet: MS-Results: numerical values associated with the economic and environmental results included in both the main manuscript and the SI, for all the considered scenarios. The results include the total price for the assessed scenarios, with and without externalities, with uncertainty ranges, as well as the environmental results for human health, ecosystems, resources, and global warming potential (GWP). MS-Tables: table reported in the main manuscript associated with the price and breakeven point of four assessed scenarios dependent on different CO2 source assumptions. SI-Tables-Economics: tables reported in the SI associated with the economic assessment of all the scenarios. SI-Tables-LCI: tables reported in the SI associated with the environmental assessment of all the scenarios. SI-Tables-AdditionalResults: tables reported in the SI associated with additional results presented in the work.