Abstract: This paper introduces component, principle and technical progress of integrated simultaneous TOF-PET/MR molecular imaging equipment. It briefly describes the integrated PET/MRI device design and composition classification. It discusses special contributions to clinical application and research with TOF-PET/MR, requirement of photoelectric component on PET detector for attaining TOF reconstruction and the prerequisite that performed simultaneous scan on PET/MR. It compares the performance differences between APD and SSPM. The problems and the challenges of PET attenuation correction with MR image parameters are introduced briefly.