But Mr Trump was found not liable for raping E Jean Carroll in the dressing room of Bergdorf Goodman.
The jury also found Mr Trump liable for defamation for calling the writer's accusations "a Hoax and a lie".
It is the first time Mr Trump has been found legally responsible for a sexual assault.
The Manhattan jury ordered Mr Trump to pay her about $5m (£4m) in damages.
Because the trial was in civil court - rather than criminal - Mr Trump will not be required to register as a sex offender.
