The flow behavior of liquid natural rubber (LNR) with reference to the effect of molecular weight, shear rate, and temperature has been studied. LNR samples were prepared by thermal depolymerization of rubber (NR) through the combined effect of mechanical, chemical, and thermal energies. High molecular weight samples, especially at lower temperatures, showed pseudoplastic behavior, whereas the low molecular weight samples were Newtonian at all temperatures. The viscosity of LNR considerably decreases with increase in temperature. The activation energy of flow was also calculated.