Abstract: Laser Ablation-Inductively Coupled Plasma-Mass Spectrometry (LA-ICP-MS) serves as an important tool for assessing variations in elemental/isotopic compositions of rocks and minerals. During LA-ICP-MS analysis, as spectrometric data acquired via mapping/line analysis are much more than those by single spot analysis, reduction and processing of the obtained data are critical. In this study, Iolite was used to handle LA-ICP-MS data acquired by line analysis on a phosphate nodule. The reduction processes include baseline subtraction, data correction using the interpolation method, and data output. The results obtained using different temporal (spatial) resolution were compared by the section output function of the software. Data reduction of line analysis using Iolite yields results similar to those obtained using wet-chemical analysis. Comparison of different temporal (spatial) resolution (10 μm, 50 μm, 100 μm) for data processing indicates that the results are best optimized when the chosen resolution (50 μm) approximates the spot size (40 μm) during analysis (in Fig.3 and Fig.4). By contrast, results obtained using lower (10 μm) or higher (100 μm) spatial resolution are either fluctuate more or lack detail. These observations indicate that Iolite is a promising tool for LA-ICP-MS data reduction. The results also emphasis the importance of using appropriate temporal (spatial) resolution for data reduction.