The accessory glands of Drosophila males are responsible for the production of proteins (Acps - Accessory gland proteins) that are transferred to the female reproductive tract during copulation. Acps participate in several steps of reproduction, being essential for fertilization. The unusually high evolutionary rates and the evidences of evolution by positive selection for some loci lead to suggestions that some Acps might be involved in speciation by causing reproductive incompatibilities between populations. Here we present the study of Acps in species the Drosophila repleta group at three different levels. First, we identify and characterize the Acp complement in D. mayaguana and compare it with the Acp set of other species of the same and distinct Drosophila groups. Within this framework, we analyze evolution of these proteins in a wide scale by looking at evolutionary rates, gene duplications, and function. Our findings show that these aspects of Acps are rather conserved and that the differences observed can be associated with biological differences between Drosophila species groups. Second, we zoom in a little bit and analyze Acp gene evolution in species of the mulleri cluster of the repleta group. By using multiple species comparisons including up to 11 species and a minimum of eight, we employ maximum likelihood methods to test whether 15 genes described here have adaptive evolution. The results show that a large percentage of Acps in the mulleri evolve by positive selection and that selective pressure may be different in different species. Finally, we descend one more level and analyze Acp sequence variation at populations of three sibling species, D. mayaguana, D. parisiena , and D. straubae. These three species show different degrees of reproductive isolation and represent an interesting model to study the potential involvement of Acps in the speciation process. By comparing a case of complete reproductive isolation with one of incipient speciation, we were able to conclude that Acp divergence does not happen following speciation, but rather it is an ongoing process within species. Our observations do not reject the hypothesis that some Acp genes play a role in the divergence of D. parisiena and D. straubae.