Obsessive-compulsive (OC) disorder (OCD) is characterized by obsessions and compulsions, giving rise to a high level of social and occupational impairments. Accumulating evidence indicates that the cause and maintenance of OCD are related to attentional bias. In this study, the neural processes underpinning attentional bias were carefully inspected for thirty participants with a high/low propensity of OC symptoms (HOC/LOC). Both behavioral and electroencephalogram (EEG) data were collected while participants were performing a dot-probe task with the threat or neutral pictures as stimuli. It was discovered from the event-related potential (ERP) results that compared to the neutral pictures, the threat pictures elicited higher amplitudes of ERP component C1 for both the HOC and LOC groups during the stimuli onset period. However, only the HOC group exhibited lower amplitudes of ERP component P1 to the threat pictures than to the neutral ones, indicating that individuals with a high level of contamination fear might divert their attention away from the threat automatically. The novel findings from the present study can pave an avenue for unveiling the complex neural mechanism associated with attentional avoidance in individuals with contamination fear.