Abstract: Polyamide 6 powders were prepared by a precipitation method in different ethanol/water mixed solvents. Morphology, thermal properties, particle size and distribution, stacking angle and density of the resulting powders were investigated by scanning electron microscopy, X-ray diffraction, differential scanning calorimetry and laser particle size analyzer. The results indicated that the interaction between the solvent and polyamide 6 increased gradually with an increase of the volume fraction of ethanol in the mixed solvents, and there was a change in morphology of polyamide 6 powders from an irregular loose structure to the regular sphere-like one. The particle size decreased to 78.81 μm and the particle distribution became narrower. There is no change in the crystal form of polyamide 6 powders. However, the thickness of crystals increased and the melting point decreased. The stacking angle of polyamide 6 powders decreased gradually, whereas its density increased gradually. The solubility parameter of the solvents exhibited an important effect on the properties of the powders.