With the development of the ever-changing magnetic resonance technology, more and more new sequences and new processing methods applicable to clinical diagnosis and identification have been unearthed, but which method can stand the test of time and become a widely used technique such as t1,t2,tof and so on, still needs to be examined by a large number of clinical experiments. Here, we introduce a whole-body diffusion technique (commonly known as pet-like imaging) and its initial clinical applications. Diffusion weighted imaging has been widely used in the clinical work in the differential diagnosis of the nervous system, especially cerebral infarction. The application of diffusion technology to body mri examination is a widely researched topic in recent years, which includes the assessment of tumor benignity and malignancy using adc value, and the assessment of radiotherapy efficacy. As a relatively mature MRI sequence, to explore its potential, it is necessary to deform the sequence. dti (diffusion tensor) technology is one of them, which mainly focuses on the post-processing analysis of dti technology. Stir-dwi, on the other hand, is trying to change the contrast of dwi and highlight the disease-sensitive features of dwi. The whole-body diffusion technique is to add ir to the traditional dwi sequence, flipping the recovery pulse, which serves to suppress part of the short T1 signal. The conventional scanning parameters of whole-body dwi sequence with added stir are similar to those of conventional dwi sequence, such as matrix: 128×128, fov: 36, layer thickness/layer spacing: 7mm/-1mm, diffusion b-value: 0, 800, etc. The difference is that it needs to set tir, flip recovery pulse to suppress part of the short t1 signal. However, the difference is that it needs to set the ti time: 160ms, the average number of times nex: 8. Generally, the volume of 240mm coverage is acquired at one time. After the axial acquisition, the diffusion image is extracted and reconstructed with 3D maximum density projection to obtain sagittal, coronal or 3-dimensional images and inverse color. The whole-body diffusion technique suppresses the magnetic resonance signals generated by muscle, fat, liver, and kidneys and highlights the contrast of the lesion area. This technique is easy to scan and does not require careful positioning of the anatomy by the operator to obtain diffusion-weighted images with high sensitivity to the lesion over a wide area, and has great potential for clinical application.