PURPOSE: To produce a backup roll with uniformity and no strain by wrapping elastic material around a core and executing main curing without inflicting substantially ununiform outside pressure against the elastic material after making the elastic material have predetermined thickness through rolling and preliminary curing thereof by a multistage calender.

CONSTITUTION: It is preferable to use a calender having more than five stages. A calender 40 is, for example, composed of a combination of steel made calender rolls 41-45 wherein mixed and rubber status of elastic material 24 which is fed from upward portion is rolled and pressed in order at four portions and is formed a predetermined thickness sheet status elastic material 55, which is wouned onto a roll 26. After winding process is finished, it is rewound in order from the roll 26 and is wound around a metal made core. Then, it is uniformly wrapped by such wrapping film as polyethylene film and is immersed in a vulcanization vessel where it receives curing, resulting in a finished backup roll.