This page describes how to import file in DXF format into GRASS using wxGUI. DXF usually contains more layers. You can convert DXF file to multi-layered GRASS vector map or import selected DXF layers as separated (single layer) GRASS vector maps.
Convert DXF layers to multi-layered GRASS vector map
File -> Import vector map -> DXF import
or from command-line
Optionally you can also import all DXF layers to single layer GRASS vector map (