Liverpool signed the young forward from Lille in July and immediately loaned him back for 2014-15 to the Ligue 1 club, for whom he has scored 15 goals in 82 appearances.
Mignolet has trained with the 19-year-old during international duty with Belgium and is backing Origi to settle quickly at Anfield.
"I have spoken with him a fair few times about next season, pre-season and how he is going to settle in - not only at the club, but also in the city," Mignolet told Liverpool's official website.
"He's looking forward to next season and I think he'll be ready for the team when he comes in.
"He's only a young player but I'm sure, from what I've seen in training with him, that he's a very good player and will do really well for us.
"He's very quick, he's got skill, he can hold the ball up and score a goal as well - what else do you want from a striker?
"He's got a good attitude to work hard in training, which is always important; he's willing to learn and accepts advice. I can only speak in good terms about him."
Origi has netted seven times in 26 league appearances for Lille this season.
