<p>As-homogenized U720Li alloy exhibits poor hot workability during the industrial cogging process involving multiple passes of deformation. To provide theoretical guidance for enhancing the product yield during cogging, the effect of pre-strain (true strain of first-pass) during double-pass deformation on hot ductility and recrystallization behavior of the alloy has been studied in this paper. The results indicate that initial grain boundaries (GBs) act as preferential failure sites during hot working. Discontinuous dynamic recrystallization (DDRX) is the dominant nucleation mechanism, and particle induced-continuous dynamic recrystallization (PI-CDRX) is the auxiliary one that occurred subsequently. In the inter-pass isothermal holding process, both the metadynamic recrystallization (MDRX) and static recrystallization (SRX) can occur. The occurrence of MDRX and SRX markedly promotes the formation of recrystallized grains in initial grain interior, which improves the second-pass deformation uniformity and the hot ductility. The greater pre-strain of 0.4 leads to a higher MDRX fraction, which more significantly lowers the flow stress of second-pass compression by 31 MPa and improves the hot workability with no cracking occurs up to the true strain of 0.6. Increasing the first-pass deformation degree appropriately is beneficial to improving the hot workability of the alloy.</p>