Steam explosion (STEX) is a promising technique to decompose natural fibre hierarchical structure down to microfibrills. Also, lignins and pectins, sugars and other components can be removed by this method. During the STEX process, fibres are chemically modified and mechanically defibrillated. At the end of the steaming process, the instantaneous release of pressure stops the reaction and separates the fibres. The objective of this work is to investigate influence of pre-treatment intensity, steam explosion process temperature and pressure on disintegration level of fibres of hemp variety Purini. The acquired results are discussed and interpreted by Fourier transform infrared spectroscopy (FTIR) and scanning electron microscope (SEM). Morphological and spectroscopic analysis of treated and untreated fibres were carried out and found that fibres treated by STEX could be usable for nanotechnologic processing.