OBJECTIVE： To study the preparation and in vitro dissolution of ethyl pepper solid dispersion. METHODS： Solvent-melting method was adopted. Using polyethylene glycol 6000 （PEG-6000） as carrier， the effects of different drug-loading ratios （1 ∶ 1， 1 ∶ 5， 1 ∶ 7， 1 ∶ 10， 1 ∶ 15， 1 ∶ 18， 1 ∶ 20） on the dissolution of ethyl pepper solid dispersion was invesigated. The stability of crude drug ethyl pepper at 85 ℃ was determined. Furthermore， differential scanning calorimetry and X-ray powder diffraction method were used to identify the existence of ethyl pepper in the solid dispersion. RESULTS： The dissolution of ethyl pepper could be improved by mixing ethyl pepper and PEG-6000 in a ratio of 1 ∶ 15， and the preparation was maintained stable at 85 ℃. The drugs part of ethyl pepper-PEG-6000 solid dispersions existed in the form of amorphous or molecular. CONCLUSIONS： The dissolution of ethyl pepper solid dispersion can be improved significantly by mixing ethyl pepper and PEG-6000 （1 ∶ 15）， and the dispersion keeps stable at 85 ℃. The study can provide reference for further study of the preparation technology of ethyl pepper preparation.