The 97-year-old actress was reportedly amused when the comic died aged 81 earlier this month because she had been so mean to other celebrities.
Zsa Zsa's husband, Prince Frédéric von Anhalt, told National Enquirer magazine: ''Zsa Zsa was watching TV when Joan died, and asked what happened.
''She said, 'She badmouthed us all. She deserved it. She's gone and I'm still here!'
''I thought that was sad but funny.''
In the 1960s, Joan - who died a week after suffering a cardiac arrest while undergoing throat surgery - used to supply the actress with jokes, but over the years she used the Hungarian-born star as the butt of her humour.
She once joked: ''Zsa Zsa has had so much plastic surgery that when she fainted the other day, no one knew whether to take her to the local hospital or to the Tupperware factory!''
Meanwhile, Zsa Zsa has suffered ill health in the last few years and has largely been bed-bound since having her right leg amputated above the knee three years ago.