We have presented the first rheological studies conducted on a series of side chain dendritic polymers (SCDP) which are produced by copolymerization of dendritic dilos of the second, third, and fourth generation with different semiregid and flexible diisocyanates. The SCDPs, consisting of polyurethane main chain and polyether side chains, obeyed time/temperature superposition. The shift factors as a function of temperature were fitted to the so-called WLF equation. Some results suggested that the dendritic side groups have a distinct effect on the elastic part of the complex modulus, whereas the effect on the viscous part seemed to be small. At low frequencies, SCDPs behaved almost Like classical viscous liquids (theory: G＇ similar to omega(2) and G " similar to omega; experiment: G＇ similar to omega(1.5-1.8) and G " similar to omega). At the intermediate frequencies, the experimental exponent was 0.8, which is higher than the theoretical value of 0.5 predicted within the Rouse model. The zero shear viscosities were generated from the low limiting values of eta＇(omega). For the dendritic macromonomers the viscosity increased with the generation number. For the dendritic polymers, however, the reversed trend was observed; the relative increase of the viscosity upon polymerization is smaller for dendritic polymers of higher generation side groups. These results were discussed in terms of the shielding effect of the dendritic side groups. Furthermore, it was demonstrated that the rheology of the SCDPs can be regulated by the choice of the diisocyanate, i.e., by changing the flexibility of the main chain.