The 30-year-old performer, producer and model, whose real name is Rakim Mayers, was arrested early on Wednesday along with two members of his entourage and his bodyguard, in connection with a fight in the city center on Sunday.
A judge agreed to prosecutors' request to extend his detention on suspicion of assault - giving them until July 19 to press charges, Stockholm district court said.
"There is a risk that if he is released he will abscond or otherwise evade prosecution or conviction," a court spokeswoman said.
Mayers' lawyer, Henrik Olsson Lilja, said the rapper denied assault and would appeal against the extended detention.
"They were attacked and have simply defended themselves," he told reporters.
"So what we will do now is to appeal to the Court of Appeal in about one or two hours, and hopefully they will have another point of view of this case."
Mayers, best known for his 2011 debut album 'Live.Long.A$AP', was arrested hours after performing at a hip hop festival in Sweden's capital on Tuesday night.
His detention has already forced the cancellation of shows in Norway and Poland. He was also due to play in Dublin on Friday and London on Sunday.
Before his arrest, Mayers, who also goes by the pseudonym Lord Flacko, uploaded videos to his Instagram account of an altercation with two men saying they had followed him and that he had not wanted any trouble.The court was still holding hearings on the detention of the two members of his entourage. His bodyguard was released on Thursday.