"Save Excel file in comma delimited format, so you have a list of coordinates, each on its own line. Edit that file to start an AutoCAD command, such as 'point' or 'pline'. Execute this script by typing script on the command line and giving name of file. Example script file:
multiple
point
x1,y1,z1
x2,y2,z2
etc."
This was the answer I got for a similar post.
Alternatively, you can use a lisp routine (I have it, but just can't recall the name right now).