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In response to the problem of moisture absorption or desorption of tobacco core materials during processing and storage, which were easily affected by environmental humidity, this paper summarized the relevant evaluation techniques for the moisture absorption characteristics of tobacco core materials. It was pointed out that the equilibrium moisture content could reflect the water holding capacity of tobacco core materials, and the testing techniques include non-destructive testing (oven method, gas chromatography, Karl Fischer method, difference method) and non-destructive testing (nuclear magnetic method, microwave method, infrared method). The former had high accuracy but took a long time. The latter had the advantage of fast and non-destructive testing, but was easily affected by sample morphology, stacking state, and other factors. Furthermore, the water status could be analyzed by water activity and low field nuclear magnetic resonance. Water activity reflected the availability of water, while low field nuclear magnetic resonance method could monitor and distinguish free water and bound water, but it was subject to interference from other hydrogen-containing components. Adsorption thermodynamics could be explored through isothermal hygroscopicity curves, adsorption models, and adsorption heat, while hygroscopicity kinetics could be explored through hygroscopicity time curves and related models. However, evaluating hygroscopicity characteristics solely from a thermodynamic or kinetic perspective might have limitations in evaluation dimensions and applicability. The future evaluation technology could combine the two to establish a more reasonable and applicable evaluation technique for the moisture absorption characteristics of tobacco core materials, providing reference for the research on the moisture absorption characteristics of tobacco products during processing and storage. [ABSTRACT FROM AUTHOR]