This study offers a conceptual model which certainly contributes to the literature of discrimination toward people living with HIV (PLHIV) and can provide the theoretical basis for future experimental research as much as intervention actions in order to achieve the aim of Zero discrimination. The health care practitioners? (HCP) attitudinal factors toward PLHIV as much as the institutional factors should be undertaken in HIV discrimination researches. While the most of researches have relatively done in the field of training and wide-awakening of HCP about HIV transmission in Iran and Asian countries, the process of forming the discriminatory intention among the HCP have not been studied yet. In order to explain the factors affecting the HCPs? discriminatory intention toward PLHIV, not only the author developed and hypothesized a model using the theory of planned behavior?s (TPB) framework but also proposed a new method of attitude measurement aims to shed a new light on predicting HIV discrimination in the health settings. The hypothesis is including: 1. The belief in the just world (BJW) among the HCPs? affects their perception of stigma as much as their prejudice and also both of them affect the discriminatory attitude toward PLHIV 2. The perception of stigma affects the HCPs? socio/cultural risk perception 3. The socio/cultural risk perception affects the HCPs? discriminatory attitude 4. The transmission risk perception affects the HCPs? discriminatory attitude 5. The discriminatory attitude affects the HCPs? discriminatory intention toward PLHIV 6. Fuzzy method compared with the existing conventional measurement methods can measure more precisely the HCPs? discriminatory attitude