Aligned carbon nanotubes (CNTs) distributed uniformly on various substrates have been synthesized by chemical vapor deposition (CVD) method. Here, we report that by first depositing a film of amorphous carbon and random nanotubes, the aligned CNTs can self-organize into arrays of long macroscopic ropes on this film. The ropes have a uniform diameter (within 5similar to30 mum) and their length can reach 0.7 min in 30 min. The CNTs in each rope are either parallel to or entangled with each other, implying high mechanical strength of these ropes, which have potential applications as a composite enhancer or a high-strength nanostructure. (C) 2002 Elsevier Science B.V. All rights reserved.