Objective The measurement of electromyography activity of diaphragm is one of the objective indicators to evaluate respiratory function, yet the electrode position during the acquisition is a great impact on the quality of diaphragm electromyography ( EMGdi) . Therefore, it is necessary to scientifically locate the position where the electrodes are placed. Methods Firstly, with the CT image of a healthy subject under deep breath, the diaphragm model of the deep-breathing position is reconstructed by the medical modeling software Mimics, the confinement area of the diaphragm is obtained by comparing the length parameter of the two-phase and the range of the electrode location is determined. Secondly, sampling point experiment of the EMGdi signal is designed, EMGdi signals of the same healthy subject are obtained in the aquisition positions with 8×8 array electrodes, the restoring period is used as the reference to calculate the motion/rest ratio after removing the ECG noise, and the quality of EMGdi signal based on the motion/rest ratio is evaluated. Results The consistency of the biomedical model and the distribution of Rijon array electrodes is verified by the sampling point experiment, and the precise position of the EMGdi signal acquisition is further determined on the basis of modeling. Conclusions The area between the intersections of 8-9 ribs of right side of the body surface is a good position for collecting the EMGdi signals and a little area on the right side is better.