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<p>The hygroscopic behavior of black carbon (BC)-containing particles (BCPs) has a significant impact on global and regional climate change. However, the mechanism and factors controlling the hygroscopicity of BCPs from different carbon sources are not well understood. Here, we systematically measured the equilibrium and kinetics of water uptake by 15 different BCPs (10 herb-derived BCPs, 2 wood-derived BCPs, and 3 soot-type BCPs) using a gravimetric water vapor sorption method combined with in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS). In the gravimetric analysis, the sorption–desorption equilibrium isotherms were measured under continuous-stepwise water vapor pressure conditions, while the kinetics was measured at a variety of humidity levels obtained by different saturated aqueous salt solutions. The equilibrium water uptake of the tested group of BCPs at high relative humidity (<span class="inline-formula"><i>&gt;</i>80</span>&thinsp;%) positively correlated to the dissolved mineral content (0.01–13.0&thinsp;wt&thinsp;%) (<span class="inline-formula"><i>R</i>²=0.86</span>, <span class="inline-formula"><i>P</i>=0.0001</span>), the content of the thermogravimetrically analyzed organic carbon (OC<span class="inline-formula">_TGA</span>, 4.48–15.25&thinsp;wt&thinsp;%) (<span class="inline-formula"><i>R</i>²=0.52</span>, <span class="inline-formula"><i>P</i>=0.002</span>), and the content of the alkali-extracted organic carbon (OC<span class="inline-formula">_AE</span>, 0.14–8.39&thinsp;wt&thinsp;%) (<span class="inline-formula"><i>R</i>²=0.80</span>, <span class="inline-formula"><i>P</i>=0.0001</span>). In contrast, no positive correlation was obtained with the content of total organic carbon or elemental carbon. Among the major soluble ionic constituents, chloride and ammonium were each correlated with the equilibrium water uptake at high relative humidity. Compared with the herbal BCPs and soot, the woody BCPs had much lower equilibrium water uptake, especially at high relative humidity, likely due to the very low dissolved mineral content and OC content. The DRIFTS analysis provided generally consistent results at low relative humidity. The kinetics of water uptake (measured by pseudo-second-order rate constant) correlated to the content of OC<span class="inline-formula">_TGA</span> and OC<span class="inline-formula">_AE</span> as well as the content of chloride and ammonium at low relative humidity (33&thinsp;%) but to the porosity of BCPs at high relative humidity (94&thinsp;%). This was the first study to show that BCPs of different types and sources had greatly varying hygroscopic properties.</p>