The 47-year-old actress had a fight with model James Gooding, 37, after dinner on Sunday (October 7), The Sun reports.
Officers were called to a Hampstead address in North London and Frost was told to report to a police station for questioning.
A police spokesperson said: "A woman, aged 47, was arrested on suspicion of common assault.
"The man did not need hospital treatment."
Frost and Gooding have been dating for several months. She has given no comment on the incident.
Frost was married to Spandau Ballet star Gary Kemp from 1988 to 1995 and to fellow actor Jude Law from 1997 to 2003.
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