The present r-fMRI study investigated the efficacy of a three-week creativity-training program called CreaTrain, a computer-based software designed to improve verbal divergent thinking. In this study we were particularly interested to see whether the training induces changes in regional homogeneity (ReHo) in a resting state condition. We focused especially on areas, which are known as key regions of the default mode network (DMN) of the brain. The sample comprised 55 participants in the age range between 19 and 34 years who were randomly assigned (though matched for gender) to an experimental group (EG) or a waiting group (WG). Both groups were tested at three different time points. The EG was trained between the first and the second test session, while the WG received the training during the second and third test session. Behavioral analyses reveal a significant interaction between time of measurement and experimental group. Accordingly, the EG which was trained between the first and the second session remained stable with respect to psychometrically determined creativity, while the WG showed decreases during this time. Only after the training the WG showed increases in creativity (between the second and the third session), whereas the EG, who did not practice any longer, exhibited decreases. At the level of the brain, the results indicate that CreaTrain has an influence on ReHo in both groups, as indicated by an increase in the right postcentral gyrus, which has been linked to attention processes in previous studies and has been associated with psychiatric personality traits such as schizotypy, which have directly or indirectly been associated with creativity. Taken together, we could demonstrate that CreaTrain is able to enhance verbal creativity, and is also associated with changes in ReHo. The present study is one of the first to explore ReHo in a resting state condition in relation to a creativity training.