Abstract: The static softening behavior of the austenite in the sheet billet during continuous casting-rolling was investigated on the Gleeble-2000 thermomechanical simulator in Bensteel. The results revealed some facts as follows by comparison. The Nb-bearing steel inhibits the static recrystallization of austenite more obviously than the steel contains no Nb, with relevant curves showing flat portion. And in the steel, the Nb precipitate inhibits the static recrystallization greater than the solid Nb solution. Moreover, the activation of static recrystallization at intervals between two pass reductions for low-carbon steel during continuous casting-rolling is more obviously than that during conventional rolling, i.e., the static softening behavior is less possible.