To provide a rotary press having a small volume sheet surface treating apparatus with small material and small expenses.

To convey a sheet 2 along units 33, 34, 5 for treating its surface, modules 25, 26 having two conveying elements 27, 29 and 28, 30 having equal circumferential speeds are provided. Each element has a gripper for grasping a front end of the sheet 2. When the gripper is rotated, the sheet is supplied one by one to the module in response to a printing period, and discharged from the module. The grippers of the elements 27, 28 are disposed at a gripper arm by a simple mechanism, and portions except the front end of the sheet is freely guided by guide elements 52, 53. The grippers of the elements 29, 30 are also disposed at the gripper arm. The sheet 2 is placed on a bent rotary support element disposed in a circumferential direction between the arms and conveyed.