According to the multimedia principle, adding relevant pictures to text is beneficial for learning. This beneficial effect is particularly true for text depicted in pictures (illustrated text information) but not for a text that is not illustrated in pictures (non-illustrated text information). The multimedia principle was examined for threat-related content: spider-fearful participants (SFs) learned about spiders. Since SFs typically inadequately process spider pictures, a beneficial effect of pictures concerning illustrated text information was not assumed for SFs but only for non-anxious control participants (NACs). Participants (N = 123) were randomly assigned to either a text-only condition or a text-picture condition and classified as SFs or NACs. In line with this assumption, adding pictures to text was not beneficial for SFs but only for NACs, particularly for illustrated text information. Thus, the perceived emotional content of pictures can serve as a boundary condition for the well-established multimedia principle.