Since the diffusion of Internet addiction has emerged in several cultural contexts, it seems relevant to study the properties of the Internet Addiction Test (IAT)-the most widely used screening instrument-across various cultures. In Italy, only one study has examined the IAT factor validity, and a comprehensive investigation of its psychometric characteristics is so far lacking. The purpose of this study was to perform a psychometric analysis of the Italian IAT. A total of 840 students (Mage=18.65 years, SD=3.85 years; 59% female) were recruited. Pertaining to scale dimensionality, the best-fit measurement model includes two factors: "Emotional and cognitive preoccupations with the Internet and social consequences" and "Loss of control and interference with daily duties" (χ(2)/df=3.38; comparative fit index=0.88; Tucker-Lewis Index=0.87; root mean square error of approximation=0.07), which together explained 45.59% of the variance. Internal consistency Cronbach's alpha values ranged from 0.83 to 0.86. Convergent validity was demonstrated, with significant correlations between IAT and Generalized Problematic Internet Use Scale 2 scores. The Italian version of the IAT was found to have good psychometric properties and a two-factorial structure. Identification of the IAT dimensions may help to define the construct better and develop intervention strategies.