On Friday a Swedish district court decided the 30-year-old artist, whose real name is Rakim Mayers, should be kept in custody while prosecutors investigate a June 30 street brawl, suspending a European tour he was performing.
Mayers' lawyer Henrik Olsson Lilja immediately challenged the decision but was denied by the court of appeals.
The lawyer told AFP on Monday his client subsequently decided to appeal to Sweden's Supreme Court.
The district court's decision means Mayers can be held in custody for two weeks, while the case is investigated. After that, it would require another hearing to extend his detention.
The rapper has already had to cancel shows in Norway, Poland, Ireland and the UK.
'Free Rocky'
Fans, as well as fellow musicians, have publicly urged Swedish authorities to release the American entertainer.
Rapper Travis Scott shouted "Free Rocky" during his performance at the Wireless Festival in London, a festival where ASAP Rocky was scheduled to perform.
Others have taken to social media under hashtags like #FreeRocky or #FreeFlacko, invoking one of ASAP Rocky's nicknames.
American hip hop duo EarthGang, who have a concert in Stockholm planned for September, tweeted "#FreeFlacko or we boycotting Sweden".
Sweden's Supreme Court is expected to decide this week whether to look at the case. It accepts only a fraction of cases submitted, taking those it thinks will provide guidance for the lower courts.
The district court had agreed with prosecutors that Mayers was a flight risk and so should be kept in custody during the investigation.
But lawyer Olsson Lilja said he believed the prosecutor had insufficiently justified the flight risk argument, and the continued custody also needed to be weighed against the consequences for his client -- both issues that could interest the Supreme Court.
"They haven't tried this issue in this way before," he added.
Brawl caught on video
Mayers was detained last week following an incident on June 30 which was partly captured in a video published by US celebrity news outlet TMZ.
The rapper, who was in Stockholm for a concert, can be seen throwing a young man into the street then aiming several punches at him while he is still down.
On July 2, Mayers posted his own videos on Instagram, which he said showed the lead-up to the clash.
In those, the young man can be seen arguing with the musician over a pair of headphones, and the artist repeatedly asks that the man and his friend stop following them.
Mayers was born in New York and had a breakthrough in 2011 with the release of the mixtape "Live. Love. ASAP". He followed that up in 2013 with the debut album "Long. Live. ASAP".