Objective To modify the positioning device for the J2205 double-color folio offset printer with the help of virtual reality. Methods First the J2205 offset printer was investigated on the spot, then the modification methods were determined and finally its structure was partitioned. SolidWorks was then used as the modeling tool to set up digital model for the offset printer, and the virtual reality modeling language VRML was employed as the interactive tool to output model on webpage. And the properties of the modified J2205 were verified. Results The results showed that virtual modification of offset printer was achieved in combination with non-lateral guide technology, and the modified J2205 saved 25% axial positioning time. It improved the accuracy of positioning and overprinting. Conclusion The virtual positioning device of J2205 could be modified repeatedly, which reduced the production cost. The position sensor could be used to help the full performance of the intelligent machine.