The rhenium–osmium (Re–Os) isotopic dating technique has been extensively applied for the precise geochronological determination of black shale formations, effectively overcoming difficulties in dating chronologically challenging strata. Recent advancements have extended this methodology to limestone systems with substantially lower Re and Os concentration, thereby providing novel technical approaches for dating carbonate sequences. Clarifying the Re distribution in limestone is critical for optimizing experimental protocols and enhancing the accuracy and precision of dating results. However, carriers of Re and Os in carbonate rocks, particularly the radioactive parent element Re, remain poorly constrained. This study investigated Permian limestone samples from Guangde, Anhui Province, via integrated mineralogical characterization using scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM-EDS) and femtosecond laser ablation-inductively coupled plasma mass spectrometry (fs-LA-ICP-MS). The analytical results indicated that Re is predominantly hosted in authigenic phases such as organic matter (OM) and pyrite. Terrigenous quartz contains little to no Re, while calcite does not host Re. These findings emphasize that Re-Os pretreatment protocols should prioritize the complete dissolution of OM and pyrite, while avoiding the dissolution of silica phases.