The Nd isotopic composition of ancient seawater recorded by marine carbonates is valuable for revealing temporal changes in continental weathering inputs and ocean circulation patterns. When analysing carbonate Nd isotopic composition, it is important to extract the primary carbonate portion without bringing in contaminative Nd released from non-carbonate phases, such as clay minerals in sample dissolution. However, there has been no specific research on the dissolution method required for neodymium isotope analysis of carbonates, whereas different dissolution methods vary significantly in selecting the appropriate acid and dissolution procedures. In this study, we conducted a set of chemical leaching experiments based on carbonate reference materials with high purity and excellent homogeneity, aiming to evaluate and optimise the dissolution method for bulk analysis of carbonate neodymium isotopes.We selected a suite of reference materials, including carbonate certified reference materials and non-carbonate minerals, such as kaolinite, montmorillonite, illite, and Fe-Mn nodules, and created a set of artificial carbonate mixed reference materials with different purities. A set of leaching experiments were carried out on these mixed reference materials. The results showed that dilute acetic acid should be preferentially selected over hydrochloric and nitric acids to dissolve carbonate rocks to obtain the Nd isotopic composition. Our study revealed that the carbonate Nd isotopes are not prone to being affected by clay minerals, as the Nd contamination released from clay minerals was limited, especially for samples with purity higher than 85% (m/m). Contrarily, the Nd contamination from Fe-Mn nodules is significant. Regarding the optimised protocol for carbonate Nd isotope analysis, we suggest a one-step leaching protocol to dissolve approximately 60% (m/m) of the total sample for sample purity above 85% (m/m). Specifically, 4 mL of 2.5% (v/v) HAc is used to dissolve 100 mg of the sample, and the leachate is analysed for Nd isotopes. For sample purity lower than 85%, we suggest a two-step leaching protocol in which 30–40% (m/m) of the sample is preleached and discarded, and another 30–40% (m/m) of the sample is dissolved to prepare for Nd isotope analysis. Specifically, 100 mg of the sample is first preleached with 2.5 mL 2.5% (v/v) HAc and then dissolved in 2.5 mL 2.5% (v/v) HAc to prepare for Nd isotope analysis. All the results indicate that accurate data of Nd isotopes can be easily obtained, which potentially broadens the application of carbonate Nd isotope. Based on the chemical leaching technique, we first report high-precision Nd isotope ratios for two carbonate standards (JDo-1 and IAEA-B-7) that can be used for quality control in Nd isotope analyses of carbonates.