Alexander Villaluna, 45, stabbed his former partner Jovi Pilapil, 39, when she was having a first date with Keith Collins, 53, in Kangnam BBQ in Westfield Hornsby in March 30, 2016.
In the NSW Supreme Court on Friday, Villaluna pleaded guilty to one count of murder and one count of wounding with the intent to cause grievous bodily harm.
Ms Pilapil, an aged-care worker, had separated from Villaluna and after that her application of AVO against Villaluna successfully issued.
She had met Mr Collins, an Irishman and a father living in Terrigal on the Central Coast online and they were attacked by Villaluna on their first date.
SBS Korean program has more.