The invention discloses a preparation process for a steel-cast roller. High-alloy steel of a working layer of the roller is in fully metallurgical bonding with graphitic steel of a core part of the roller. The high-alloy steel comprises, by weight, 0.5% of C, 0.5% of Si, 0.5-0.6% of Mn, 4.5% of Cr, 1.1% of Ni, 0.7% of Mo, 0.04% of Re, less than or equal to 0.03% of P, less than or equal to 0.03% of S, and the balance Fe; the graphitic steel comprises, by weight, 1.5% of C, 1.8% of Si, 0.5% of Mn, 0.6% of Ni, less than 0.2% of Cr, less than 0.3% of Mo, less than 0.03% of P, less than 0.03% of S, and the balance Fe. By means of the preparation process for the steel-cast supporting roller, the obtained roller has the advantages that the abrasion resistance and the toughness of the working layer of the roller are good, the anti-accident ability is high, the service life is long, and accordingly the manufacturing cost of the roller is reduced.