The idea that words used by people are indicative of their personality has been established in several studies. In this study, we ask whether song lyrics of different music genres (e.g., punk) are associated with different personalities. We tested the hypotheses that (1) personalities are associated with lyrics of various music genres and that (2) personality, as expressed in song lyrics, may be used for the classification of songs into genres. We used a database of 17,495 songs categorized into music genres and 2468 essays written by students whose personalities have been assessed through the five factor model of personality. The method uses sophisticated tools of Natural Language Processing. The research hypotheses were confirmed and it was found that it is possible to predict participants’ personality based on the similarity of their writing style to the style of various music genres, and that songs can be automatically classified into music genres based on the similarity of those songs to personality factors. Therefore, it is possible to conclude that the lyrics of music genres can be used to predict personalities, and conversely, personalities can be used for genre identification and classification.