Clone this repo into custom_nodes folder.
Install dependencies: pip install -r requirements.txt or if you use the portable install, run this in ComfyUI_windows_portable folder:

python_embeded\python.exe -m pip install -r ComfyUI\custom_nodes\comfyui-vace-preprocessors\requirements.txt

Models

You might already have some of the models from other sources, double check:

Create a salient directory in ComfyUI/models and add u2net.pt file from https://huggingface.co/ali-vilab/VACE-Annotators/resolve/main/salient/u2net.pt?download=true
Create a sam2 directory in ComfyUI/models and have these files there https://huggingface.co/ali-vilab/VACE-Annotators/tree/main/sam2
Create a grounding-dino directory in ComfyUI/models and have these files there https://huggingface.co/ali-vilab/VACE-Annotators/tree/main/gdino and rename GroundingDINO_SwinT_OGC.py to GroundingDINO_SwinT_OGC.cfg.py