How to delete lines of a text file based on another text file?

I have 2 TXT files with with 8 columns in them(tab separated). First file has 2000 entries whereas 2nd file has 300 entries.

The first file has ALL the lines of second file. Now I need to remove those 300 lines (which are in both files) from first file so that first file's line count become 1700.

I tried with sort and comm commands but it worked only on single-column files. As my files are multi column files, Its not working.

any help would highly be appreciated.

Thanks very much.

awk 'FILENAME=="file2" {arr[$0]++}
       FILENAME=="file1"  {if($0 in arr) {next}; print $0 }' file2 file1 > outputfile

I would simply:

grep -v -x -f 300_file 2000_file > 1700_file