The present invention relates to an amorphous form of Apemilast, its methods of preparation and its application, and the X-ray powder diffraction (XRPD) pattern of the amorphous form contains three broad peaks at a diffraction angle between 2.0 to 50.0 expressed in degrees 2θ, but not contain sharp diffraction peaks. The present invention also related to solid dispersion of amorphous Apremilast and its method of preparation, and it contains amorphous Apremilast and two or more pharmaceutical excipients, and the weight ratio of Apremlaist to all of pharmaceutical excipients is 1:0.1∼100. The amorphous form and amorphous solid dispersion of Apremilast of the present invention increases the solubility of Apremilast and improves bioavailability of the drug product. As compared to the existing crystalline forms of Apremilast, its solubility increases significantly, which improves bodys absorption of the drug and makes it more efficacious in the clinical therapeutic treatment of diseases. Under the stress test conditions, the amorphous material can maintain good physical and chemical stabilities. The preparation method of amorphous Apremilast according to the present invention is simple to operate and easy to implement.
