We describe a novel solution-based acoustic manipulation technique for the parallel alignment of carbonnanotubes on solid substrates. The acoustic radiation force and acoustic streaming, which are generated fromthe transmission of ultrasound through a fluid, facilitate the mobility of the nanotubes and result in theiralignment on the substrate surface. A theoretical model considering various forces and resultant torques exertedon the nanotubes is first proposed for analyzing the alignment through a fluid medium.