The Black Lives Matter march went through central London to the Houses of Parliament at about 20:00 BST.
The marchers were heard to shout “Hands up, don’t shoot” as they carried banners through the capital.
The march is in response to the fatal shootings of Philando Castile in Minnesota and Alton Sterling in Louisiana.
The Black Lives Matter London Movement was founded by 18-year-old sixth form student Marayam Ali.
Further protests are planned in Windrush Square, in Brixton, on Saturday and Oxford Circus on Sunday.
Five police officers were killed on Thursday during a march in Dallas, Texas, organised to protest against the shooting of black men by police.
A gunman was subsequently killed using an explosive device and was named as 25-year-old Micah Johnson.
Three people are in custody but it is not clear if there were other gunmen.
Source: BBC News