Curation by Chiho Kim, Tran Doan Huan, Sridevi Krishnan, and Rampi Ramprasad. Hybrid organic-inorganic perovskites (HOIPs) have been attracting a great deal of attention due to their versatility of electronic properties and fabrication methods. We prepare a dataset of 1,346 HOIPs, which features 16 organic cations, 3 group-IV cations and 4 halide anions. Using a combination of an atomic structure search method and density functional theory calculations, the optimized structures, the bandgap, the dielectric constant, and the relative energies of the HOIPs are uniformly prepared and validated by comparing with relevant experimental and/or theoretical data. We make the dataset available at Dryad Digital Repository, NoMaD Repository, and Khazana Repository (http://khazana.uconn.edu/), hoping that it could be useful for future data-mining efforts that can explore possible structure-property relationships and phenomenological models. Progressive extension of the dataset is expected as new organic cations become appropriate within the HOIP framework, and as additional properties are calculated for the new compounds found. When using this data, please cite the original publication: Kim C, Tran HD, Krishnan S, Ramprasad R (2017) A hybrid organic-inorganic perovskite dataset. Scientific Data 4: 170057. https://doi.org/10.1038/sdata.2017.57Additionally, please cite the Dryad data package: Kim C, Huan TD, Krishnan S, Ramprasad R (2017) Data from: A hybrid organic-inorganic perovskite dataset. Dryad Digital Repository. https://doi.org/10.5061/dryad.gq3rg