The aim of this study is to develop a web-based HIV testing belief Inventory (wHITBI) and to examine the reliability and validity of the scores of the instrument. Steps for developing the item pool are described. Students from one major university in the south-eastern US were recruited. The sample (n = 440) was randomly split into equivalent halves for an exploratory factor analysis (EFA) and confirmatory factor analysis (CFA). The EFA showed that the wHITBI items were loaded in a way consistent with the four theoretical constructs: perceived benefits, concerns of HIV risk, perceived stigma, and availability/accessibility. CFA using LISREL 8.7 confirmed the structure of the inventory indicated by good model-fit indices (χ²/d.f. = 1.79; root mean square error of approximation = .06; non-normed fit index = .89; comparative fit index = .90; incremental fit index = .91; root mean square = .07), with all factors loaded significantly (p < .001). The composite reliability ranged from .67 to .76. The results also showed that these scales can distinguish well among HIV-tested and never-tested students. The validated wHITBI has implications on future applications for the development and evaluation of HIV prevention and education programs delivered via the Internet.