Andy Anokye, whose stage name is Solo 45, has been has been charged with 29 counts of rape after new allegations came forward.
Anokye, 31, was initially charged with two counts of rape, one count of false imprisonment and one count of causing actual bodily harm.
He has now been charged with a further 27 counts of rape after three more people came forward with allegations, police have said.
The star is part of north London grime group Boy Better Know.
The grime crew also includes Skepta, Wiley, JME and – as of last year – Drake.
Anokye – who found fame with 2014 track Feed Em To The Lions – had pleaded not guilty to the earlier charges at Bristol Crown Court.
All the original charges related to one victim.
He is due to stand trial on 16 April 2018.
A spokesman for Avon and Somerset Constabulary said: “Detectives are still keen to speak to anyone who may be able to offer information which may assist an on-going investigation concerning Mr Anokye.”