In terms of an attentional bias, attention of phobic subjects seems to be more readily drawn to threatening than to neutral stimuli. To analyze these early attentional processes within spider phobics, the present study investigated a spider phobia specific dot probe paradigm performed with the measurement of electrocortical activity for the first time. Therefore, two images (spiders, disgust and neutral) were presented parallel on a screen for 100 or 1500 ms and the response to a small dot (target), which replaced one of the images, got measured. The target appeared either congruent (following a spider or disgust image) or incongruent (following a neutral picture) and participants should indicate the posttion oft he target via mouse click (left or right). The reaction times and electrocortical activity (ERP data) of the subjects got measured. It was found, that the duration of the image presentation had an effect on the reaction times and electrocortical activation of the subjects. Both groups showed faster responses to the target after a long presentation (1500 ms) of spider and disgust pictures, compared to short trials. Moreover, both conditions, long congruent trials with spider and disgust pictures, as well as long incongruent passages with disgust pictures, led to higher occipital P1 components in spider phobics. A longer duration of presentation of unpleasant stimuli appears to result in faster reactions and higher occipital P1 components. In addition, in this sample, the disgust propensity and disgust sensitivity was collected and showed significant differences between the groups: spider phobics showed higher disgust propensity and disgust sensitivity, compared to the control group and rated the spider pictures as equally disgusting than disgust images. The importance of disgust within the spider phobia could be confirmed. Nevidence of an attentional bias or reflexive attentional processes in spider phobics could be found.