According to the coding problem in the region of interest (ROI) for man-in-the-loop，a method of dynamic ROI coding is proposed，this method uses the characteristics of distortion-rate function and convex function. The different target bit-rates are set respectively for ROI and BG in the same layer. Every coding layer can control ROI and background bit-rate，so ROI can obtain the higher coding quality，the ROI and priority can be specified and modified during the coding process. The experimental result shows that the method meets the needs of ROI dynamic change during the remote control operation.