Introduction: Obesity is one of the diseases in modern and industrial life which is increasing with the rise of social facilities. Considering the previous studies, cognitive factors (attentional bias) play major role in the failure of dieting people. The present study investigates the subliminal attentional bias in dieters compared to nondieters.
 Materials and Methods: This causal-comparative study conducted clinics of Ghaem and Imam Reza hospitals and the clinic of faculty of Education Sciences and Psychology of Ferdowsi University of Mashhad in 2011. Participants were dieters (n=30) and nondieters (n=30) in which the ratio of genders are the same. Individuals, between 20 to 50 years old, were categorized into two groups of dieters and nondieters. To measure the attentional bias, the combine Stroop test was done and for each participant, two versions of pictorial and lexical stroop test were used. Data analyzed by MANCOVA and SPSS software version 20.
 Results: The results showed that there are not any significant differences between the interference mean scores of low-calorie (P=0.28)/high-calorie (P=0.57) food images and the low-calorie (P=0.307)/high-calorie (P=0.202) food names in the two groups.
Conclusion: It seems that subliminal food stimuli may not cause attentional bias in dieters in comparison with non-dieters.