Paltrow, who is married to Coldplay frontman Chris Martin, was speaking prior to performing at last night's Oscars.
Speaking to Project Runway's Tim Gunn on the red carpet, she explained: "I think [Jay-Z and I would] be a good combination. He is a genius - and I'm his biggest fan."
When asked what husband Martin would think of the collaboration, she responded: "I think [he would be] very happy."
Martin has previously worked with Jay-Z on a track titled 'Beach Chair' from the rapper's 2006 album Kingdom Come. The hip-hop star also features on an edit of Coldplay's 'Lost'.
Paltrow recently performed at the Grammy Awards with Cee Lo Green, singing his hit 'F**k You!'.
The Iron Man actress entered the UK singles chart for the first time on Sunday, following her stint on Glee.