The transcription factor FOXP2 is a regulator of vocalization-, speech-, and language-related phenotypes in human and non-human species. The FOXP2 protein contains multiple domains including a DNA-binding forkhead domain, a zinc finger domain, a leucine zipper, and N-terminal polyglutamine (polyQ) repeats. We have recently found that the FOXP2 N-terminal polyQ region drives the liquid-liquid phase separation (LLPS) of the protein. FOXP2 LLPS is regulated by the evolutionary length variation of the polyQ repeats and has a role in modulating the transcriptional activity of the protein. The potential role of other parts of the protein in the LLPS process is not clearly understood. We have undertaken a molecular dissection approach to investigate the possible interplay between the polyQ region and other FOXP2 domains in the LLPS process in the cellular context. Our findings further clarify the molecular underpinnings of the FOXP2 LLPS process, with important implications for the regulation of the molecular function of the protein.