Format conversion is enabling function at the interface of different networks with different optimal modulation formats.Meanwhile,multi-channel signal processing function has its special significance for dense wavelength division multiplexing networks.In this paper,we designed and fabricated a delay interferometer cascaded with an arrayed-waveguide grating based on silicon on insulator.The 4-channel return-to-zero on-off keying(RZ-OOK) to non-return-to-zero on-off keying(NRZ-OOK) and return-to-zero differential phase shift keying(RZ-DPSK) to non-return-to-zero differential phase shift keying(NRZ-DPSK) format conversions at 40 Gbit/s were realized with this integrated device,the output eye diagrams showed a good conversion performance.Thanks to the mature fabrication technology,this device shows great potential for its small size,low power consumption and possibility of monolithic integration.