Background: This study aimed to identify the most important factors of changing pattern of drug abuse from opium to methamphetamine in Iranian drugdependent women. Materials and Methods: This study was a phenomenological study. The data were analyzed by the 7-step Colaizzi method. Subjects selected from patients who were referred to addiction rehabilitation residential center of welfare organization in Bojnurd city located in northeast Iran. Results: We found 8 conceptual classes, and 32 codes from the analysis of data. The individual factors were as follow: elevation of mood, obtaining more pleasure, increasing energy and improving performance, relief of physical pain, and sensation seeking. Conclusions: Depth review and analyses of interviews revealed that individual factors are the most important factor in crystal meth abuse.