The multifaceted courtship display of male satin bowerbirds (Ptilonorhynchus violaceus) involves several elements that have been studied in detail. However, one of their most unusual behaviors, bower painting, has received little attention. Here, I propose two hypotheses for the function of paint and use multiple approaches to test predictions made by these hypotheses. First, I assessed how natural variation in paint quantity is related to other display traits, male mating success and male physical condition. Also, I used experimental methods including a paint removal and paint transfer experiment to investigate how birds responded to changes in the quantity and quality of bower paint. I found that males with more paint had better overall bower display quality and that fewer females returned to and copulated with males whose paint was removed. These results suggest that females may assess paint quantity during mate searching and demonstrate that paint influences male attractiveness.