Nanostructured SiC has been elaborated from coarse grained SiC by mechanical attrition. Milling time ranged from 1 h to 14 h. Crystallites sizes and microstrains have been determined from X-ray diffraction peak profile analysis using a one peak method . According to this method, the average crystallite size calculated from the (11.0) and (10.4) 6H-SiC reflections is less than 50 nm with a milling time of one hour. Up to 6 h milling time, crystallite sizes determined from these two peaks are very close, indicating that crystallite size evolution versus milling time is nearly identical for these two crystallographic directions. We observe a strong decrease of the crystallite size up to 3 h milling time. A saturation value is reached after 6 h milling time, associated with a strong increase of microstrains.From density-pressure measurements performed in uniaxial compression, the powder's compressibility behavior appears to be strongly related to changes in powder morphology and granularity during ball milling. The evolution of the powder morphology was followed by scanning electron microscopy. The iron contamination level by the steel vial and balls was controlled by X-ray microanalysis.