Abstract: To address dust pollution in coal mines and overcome the drawbacks of traditional chemical dust suppressants, such as strong environmental dependence, high ecological toxicity and susceptibility to secondary pollution, a novel eco-friendly microcapsule dust suppressant was prepared via microencapsulation technology. Using guar gum as the main wall material and corn straw biochar as the core material, the preparation adopted the emulsification-coacervation method combined with stearic acid hydrophobic modification and citric acid crosslinking treatment. The microcapsules feature a compact surface structure and favorable interfacial bonding. The corn straw biochar core possesses well-developed porous structures and a high specific surface area, enabling efficient adsorption of moisture and dust particles. The guar gum wall material forms a three-dimensional gel network after crosslinking with citric acid, which endows the product with excellent wind erosion resistance and sustained-release performance. Test results show that the microcapsule dust suppressant exhibits remarkably better wind erosion resistance than conventional methods including water sprinkling and sodium dodecylbenzene sulfonate dust suppression, with a maximum wind erosion mass loss rate of only 8%. The dust suppression efficiencies for total dust and respirable dust reach 90.6% and 83.4% respectively, more than twice those of traditional water sprinkling. The 28-day biodegradation rate of the microcapsule product is 64.3%, demonstrating favorable eco-friendliness and compliance with environmental standards. Field tests show that its water consumption is merely 20% of that of conventional water sprinkling, with the overall cost reduced by 22%, and the dust suppression duration extended to over 12 hours. Relying on the adsorption of porous core material, barrier protection of wall material and environment-responsive release mechanism, and this technology establishes a three-way synergistic dust suppression system of “moisture absorption-consolidation-barrier”. It integrates long-term dust suppression performance and environmental friendliness, and realizes the organic combination of high-efficiency dust control and green development. This work provides an innovative, economical and sustainable solution for dust treatment in coal mines and other complex working environments.