The actor, best known for his part as Walford's Minty Peterson, has been filming at the Channel 4 soap's base in Liverpool over the past few weeks.
Show bosses are keeping tight-lipped over Parisi's storyline, but Digital Spy understands that he is playing a character named Walt.
Hollyoaks fans will see Walt on screen for a handful of episodes in June.
Parisi teased his Twitter followers with the news that he had secured another soap job a few weeks ago.
He said at the time: "Just on my way back to London after my first day on another soap! Overalls are a possibility, ho hum! Don't panic it's just a few eps, blink and I'm gone, but it's fun and they are a really lovely bunch."
Parisi played EastEnders' Minty between 2002 and 2010. More recently, he has been seen as Fred on BBC One's Call the Midwife.
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