Emotions in traffic, especially anger, are factors increasingly focused on by research. However, even though the use and popularity of bicycles as means of daily transportation especially in urban areas have been growing, the concept of cycling anger defined as the propensity of cyclists to get angry in traffic has been rather neglected. For further insight into cycling anger, this study examined similarities and differences between professional bicycle messengers (N=123) and regular cyclists (N=421). Among other questionnaires the Cycling Anger Scale (CAS) measuring cycling anger caused by police interaction, car interaction, cyclist interaction, and pedestrian interaction, was used. Results showed that bicycle messengers experienced generally and on the subscales cyclist interaction and car interaction less anger than regular cyclists. Moreover, gender differences between regular cyclists became apparent: male cyclists showed overall higher anger scores. For both cyclists groups significant correlations between cycling anger and self-reported risky cycling behaviour was observed.