The low aqueous solubility of dapsone (DPS), a widely used anti-acne drug, greatly limits its biological efficacy, especially the anti-inflammatory effect. This article has applied the nanocrystallization technique to increase the surface area which consequently improves the solubility, dissolution, and anti-inflammatory effect of dapsone. Span-stabilized dapsone nanocrystals (DPS-NCs) have been prepared using solvent-antisolvent crystallization technique. The obtained nanocrystals (NCs) were characterized by FTIR, DSC, and X-ray. The morphology, particles surface, sizes, and surface charge of DPS-NCs were examined by TEM, SEM, and zetasizer, respectively. Additionally, the in vitro solubility, dissolution, and anti-inflammatory of the DPS-NCs were investigated. DPS-NCs were spherical in shape with smooth surfaces and had a hydrodynamic particle size of about 149±4.73 nm. The saturated aqueous solubility of DPS-NCs was 1.8 ± 0.05 mg/mL which was about 6 fold higher than that of a pure drug and showed improved in vitro dissolution. The used excipients did not interact chemically with the drug as indicated by DSC and FTIR. X-ray diffraction and TEM imaging confirmed that the produced nanocrystals (NCs) still have a certain degree of crystallinity and did not completely convert to the amorphous state. The in vitro anti-inflammatory of DPS-NCs greatly improved compared to pure drug. DSP-NCs could be considered a novel, promising, and effective therapeutic option for the treatment of acne as well as for relieving the accompanying inflammation.