PURPOSE: To provide a method and device for manufacturing a homogeneous irregular shaped strips having small difference of hardness by individually controlling the rolling speeds for a thick plate part and thin plate parts.

CONSTITUTION: At the time of manufacturing the irregular shaped strip by rolling a material 9 to be rolled, cylindrical work roll 4 for rolling the thin sheet parts are made so as to be linked to the rotation of a back-up roll 1 and a work roll 3 for rolling this strip is made so as to be linked to the rotation of a back-up roll 2 and a work roll 5 for rolling the thick plate part is formed into one body with the shaft of the work roll through a universal joint 8. Then, by respectively and individually controlling the rotational speeds of the work roll 5 for rolling the thick plate part and the cylindrical work roll 4 for rolling thin sheet parts, both circumferential speeds are adjusted so as to be approximately same.