The 33-year-old mum-of-one was said to be dating Brokeback Mountain star Jake (32) for the past number of weeks.
However, a representative for the actress stated "that is not true at all".
The couple were rumoured to have shared several romantic dinners together -- said to be masterminded by Katie's former Dawson's Creek co-star Joshua Jackson.
Speculation about the pair began after Jake went to see her Broadway show Dead Accounts.
But well-wishers hoping for a new romance for newly single Katie were left disappointed when her publicist quashed reports.
It appears the Katie is happy to just focus on her six-year-old daughter Suri and her acting career.
She shares custody of Suri with former husband Tom Cruise (50).