EXCLUSIVE

Frances Bean Cobain is pulling the plug on her marriage, and she wants to make it clear to her husband ... he may look like Kurt Cobain, but his money is all hers.

Frances married Isaiah Silva back in June of 2014. 31-year-old Isaiah is in a rock band called The Eeries.

They've been together for 5 years but married for less than 2, and it seems 23-year-old Frances is nervous enough to include in her divorce docs that Isaiah should not even think about making a money grab for her dad's estate -- reportedly valued at $450 MILLION.

She indicates in the docs she's open to paying him spousal support.