Lauren Griffiths, 21, was found at a flat in Glynrhondda Street at around 6.30pm on Tuesday, April 30.
A 22-year-old man, known to Lauren, was arrested that evening in connection with her death and later released on police bail pending further enquiries.
Following new information, he has been re-arrested at his home address in Wrexham on suspicion of Lauren’s murder.
Detective Inspector Stuart Wales, from South Wales Police Major Crime Investigation Team, said: “It is three months today since Lauren’s body was sadly found at her flat in Cathays and since that time we have been conducting an extensive and thorough investigation into her death.
“As a result of these enquiries, we have re-arrested a suspect and he is being questioned by South Wales Police detectives at a police station in North Wales.
“We continue to receive information from the public, for which we are extremely grateful, and are keen to hear from anyone else who can offer information.”
Lauren’s family, who live in the Oswestry area, have been updated on today’s developments and continue to be supported by family liaison officers.
In a statement, they said: “The past three months have been unbearable.
“We all miss Lauren so much, she truly was our ray of sunshine. Our lives have been torn apart.
“Lauren was due to go on our family holiday in August which inevitably had to be cancelled leaving her younger siblings confused and upset.
“This holiday was an annual tradition that has been broken. This is how we are feeling – broken.
“We are crying out if anyone does have information, please contact South Wales Police.”
Further tests and enquiries are being made to establish the exact cause of Lauren’s death.
Detectives are particularly keen to speak to anyone who knew Lauren and may have spoken to her between March 2018 and April 2019.
Alternatively information can be submitted via the police major incident public reporting site via this link: https://mipp.police.uk/operation/62SWP19A84-PO1