In order to clarify the effect of Nb content on austenite recrystallization, low carbon steel was studied and discussed by means of thermal simulation test machine and metallographic analysis. The results showed that the critical strain of dynamic recrystallization increased with the increase of strain rate and decreased with the increase of deformation temperature.The effect of inhibiting dynamic recrystallization was more obvious, when Nb mass fraction was increased to 0.05%. In addition, reducing the deformation and the interval time, and increasing the content of Nb will also reduce the static recrystallization volume fraction and hinder the occurrence of static recrystallization.