Abstract: In order to improve the accuracy of iron ore and other bulk mineral products trade and shipping stowage measurement，aiming at the problem of insufficient reliability of measurement results caused by various operation links and complex influencing factors in the determination of iron ore stowage factor by standard measuring box method，according to the technical specification SDLH-WI / JC-104- 2020，the determination of iron ore stowage factor and the evaluation of measurement uncertainty are sys⁃ tematically carried out.The main sources of uncertainty are analyzed and identified by multiple sets of paral⁃ lel tests. Class A is used to evaluate the repeatability of quantitative measurement，and Class B is used to evaluate the volume calibration and mass measurement components of the analysis chamber. The complete quantitative data of uncertainty components are obtained. The combined standard uncertainty of this meth⁃ od is 0.001 236 m3 /t，and the expanded uncertainty is 0.002 m3 /t（k=2）. It is confirmed that the measure⁃ ment repeatability is absolutely dominant in the combined uncertainty.The evaluation method proposed in this study can effectively support the accuracy verification of the measurement results of iron ore stowage factor，and provide practical technical reference and method basis for uncertainty analysis of the subse⁃ quent bulk mineral products stowage factorand quality control.

Key words: iron ore, stowage factor, standard measuring box method, uncertainty evaluation