Background: The root of Angelica gigas Nakai is used as a traditional herbal medicine in Korea for the treatment of many diseases. However, the poor water solubility of the active components in A. gigas Nakai is a major obstacle to its bioavailability. Methods and Results: This work aimed at enhancing the solubility of the active compounds of A. gigas Nakai by a chemical (using a surfactant) and physical (hot melt extrusion, HME) crosslinking method. Fourier transform infrared spectroscopy revealed multiple peaks in the case of the extrudate solids, attributable to new functional groups including carboxylic acid, alkynes, and benzene derivatives. Differential scanning calorimetry analysis showed that the extrudate soilid had a lower glass transition temperature (Tg) and enthalpy (ΔH) (Tg : 43℃, ΔH : < 6 J/g) as compared to the non-extrudate (Tg : 68.5℃, ΔH : 123.2) formulations. X-ray powder diffraction analysis revealed the amorphization of crystalline materials in the extrudate solid. In addition, enhanced solubility (53%), nanonization (403 ㎚), and a higher amount of extracted phenolic compounds were achieved in the extrudate solid than in the non-extrudate (solubility : 36%, nanonization : 1,499 ㎚) formulation. Among the different extrudates, acetic acid and span 80 mediated formulations showed superior extractions efficiency. Conclusions: HME successfully enhanced the production of amorphous nano dispersions of phenolic compound including decursin from extrudate solid formulations.