The aim of this work is to study the effect of thyroxine on the restoration of regenerative capacity in two metamorphic stages (56 &58) of the Egyptian toad, Bufo regularis Reuss, after amputation at the mid-shank level. Thyroxine failed to enhance limb regeneration in both stages, where 73.07% and 2.6% of the treated cases of stages 56 & 58 produced toed limbs respectively 72.33% and 4.3% of the control animals respectively. Differentially, thyroxine had no enhancing effect on the number of toes in the regenerating limbs, where 1.92% and 26.92% of the treated cases produced five and four toes each compared with 2.13% and 40.4% of the control animals of stage 56 respectively. Also, 2.6% of the treated cases of stage 58 produced one toe each compared with 4.3% of the control animals. Histological examination revealed the formation of large masses of cartilage that were added to the stump skeleton resulting in the elongation of the regenerates, where 59.7% of the treated cases of stage 58 produced elongated regenerates in the form of part of foot compared with 55.7% of the control animals. It may be suggested that thyroxine treatment of amputated limbs of the prometamorphic stage (stage 56) and the metamorphic stage (stage 58) failed to enhance limb regeneration and resulted in partial retardation of the regenerative ability probably due to the presence of high concentration of thyroxine within the bodies of tadpoles which in turn accelerated the process of metamorphosis. On the other hand, thyroxine enhanced terminal differentiation of chondrocytes and formation of large masses of cartilage.