Roos, whose Derby contract expires on the finish of the month, has signed a pre-contract settlement to affix the Dons.
The Dutchman stored seven clear sheets in 18 appearances for the Rams final season.
Derby County goalkeeper Kelle Roos is becoming a member of Aberdeen on a two-year deal.
Aberdeen had been searching for a goalkeeper following the departure of Gary Woods on Friday. His deal was terminated with 12 months remaining on his contract.
The Dons had been closely linked with Vaclav Hladky, who performed for Ipswich City in a 7-0 pleasant win in opposition to Needham Market.
Hladky beforehand performed for St Mirren throughout Aberdeen supervisor Jim Goodwin’s time in cost.
Roos joined Derby County from Nuneaton City in 2014. He has had 5 mortgage spells away from Satisfaction Park at Rotherham United, AFC Wimbledon, Bristol Rovers, Port Vale and Plymouth Argyle.
Aberdeen boss Jim Goodwin was happy to finalise a deal for the 30-year-old.
He mentioned: “Kelle brings with him a wealth of expertise and he’ll assist to reinforce the goalkeeping workforce now we have on the membership.
“It’s very important we add high quality to the squad this season so we’ve taken the time to establish the proper gamers with the attributes we really feel may have a constructive affect. Having performed a big variety of video games within the English Championship, Kelle ticks all these packing containers for us.
“He’s a really assured character and I’m certain he might be a well-liked addition to the dressing room.”