Abstract: Thermal simulation compression tests were carried out on domestic F690 marine steel under different deformation amounts (0–50%), deformation temperatures (800, 900, 1 000 ℃) and strain rates (0.1, 0.01, 0.001 s⁻¹) by thermal simulation testing machine, and the effects of different deformation conditions on the microstructure and properties of test steel were studied. The damage parameters and recrystallization under different deformation conditions were analyzed with Deform-3D finite element software. The results show that the steel deformed under different deformation conditions all underwent work hardening at the initial stage of deformation, and with the increase of true strain, the flow stress firstly increased, then gradually decreased after reaching the peak, and finally became stable. The flow stress decreased with the decrease of strain rate or the increase of deformation temperature. The damage value after deformation was small at high deformation temperatures and low strain rates, and the dynamic recrystallization volume fraction was large at high deformation temperatures and high strain rates obtained by simulation. Dynamic recrystallization mainly occurred at high deformation temperature and moderate deformation amount. The bainite phase changed from discontinuous dynamic recrystallization to continuous dynamic recrystallization with the increase of strain rate, the grain refinement degree also increased, and the grain size inhomogeneity decreased. At high strain rates, a relatively high deformation temperature was preferred, which could weaken work hardening effect and improve plasticity of the test steel.