Elution fractionations of broadly molar mass-distributed, hyperbranched poly( urea-urethane)s with OH- and Ph- end groups were carried out to obtain a number of macromolecular samples possessing different molar masses at the same chemical structure. The characterization of the polymers was performed by SEC, MALLS, H-1-NMR, MALDI-TOF-MS and viscosity measurements. Modifications of the OH- end groups of the polymers were carried out. We observed a strong influence of the end groups on the solution behaviour of the hyperbranched samples. The molecular shape of the hyperbranched polymers in solution was compared to their linear analogue using the Kuhn-Mark-Houwink-Sakurada relationship. The calculated contraction factors between 0,15 and 0,7 depending on the molar masses correspond to a very compact structure of the modified branched polymers at high molar masses.