Abstract: Finite element simulation on rolling process for 30CrMo steel 350 mm x 450 mm casting bloom with surface 1 150 ℃ and canter 1 240 ℃ rolling to 0230 mm bar products is earned out to study effect of rolling parameters including single pass 10% ~ 30% reduction ratio, double pass reduction 50 mm-50 mm, 10 mm-90 mm and 90 mm-10 mm at total reduction 100 mm on canter density of bar. Results show that with single pass reduction ratio 20% the canter density has definite improvement, and with 30% canter density has obvious improvement ； at total' reduction ratio 100 mm, the improvement of canter density is not obvious by 50 mm-50 mm rolling process, but the improvement of canter density is most obvious by 10 mm-90 mm rolling process. The rolling results at situ are corresponding to the simulation results.