Sedimentary sulfur isotopic records constrain reconstructions of seawater sulfate evolution, pyrite burial, microbial sulfur metabolisms, ocean redox, anoxia, and Earth-system feedbacks. These reconstructions require isotopic values to remain linked to sulfur phase, age, locality, and source context. Here, we present the Deep-time Sediment Sulfur Isotopes database (DSSI), a compilation of marine sedimentary sulfur isotopic records in which each isotopic value remains linked to its sulfur phase and associated geological context, spanning 4,061–0 Ma. The released v1.0 datasheet (Guo et al., 2026; <a href="https://doi.org/10.5281/zenodo.21675881" target="_blank" rel="noopener">https://doi.org/10.5281/zenodo.21675881</a>) contains 78,070 rows and 136 public fields; 64,990 rows contain at least one numeric sulfur isotopic value. Sulfur isotopic values are stored in unified isotopic fields and linked to a hierarchical phase classification comprising sulfur category, sulfur component, and sulfur carrier. The release also preserves stratigraphic age, modern and reconstructed paleogeographic coordinates, lithology, depositional setting, analytical method, and auxiliary geochemical information, where available. This structure supports source-traceable spatial and temporal synthesis that distinguishes sulfur phases without separating isotopic values from the geological metadata needed to interpret them.