For extremely asonmetric n-hexyl(n-decyl)phosphate (HDeP), n-hexyl(n-dodecyl)phosphate (HDoP), and n-hexyl(n-cetyl)phosphate (HCeP), the effect of the long chains on the dynamic behavior of their aggregate structures in water was examined by cryo-TEM imaging, SANS, and X-ray diffraction techniques. The ayo-TEM images demonstrated the complex and dynamic behavior of,the aggregates, and its dependence on the length ofthe long-chain. Application of the one-dimensidnal aggregate theory to the SANS results led to the conclusion that the existence of a limiting size also depended on the length of the main long-hydrocarbon. chain and-affected strongly the dynamic behavior of the aggregates, causing breakage of thread-like micelles or ribbon-like aggregates. The X-ray diffraction patterns of the lyotropic liquid crystalline samples of HDeP and HCeP were used to estimate the aggregate structures of this limited size.