The 23-year-old midfielder completed a move to the Serie A side from PSV on Tuesday for a fee believed to be around 17 million euros.
The 23-year-old signed for the Serie A outfit for a fee believed to be around 17 million euros, with another 2 million euros to come through add-ons, and the Netherlands international is thrilled to have joined Rudi Garcia's side.
"I'm really happy I'm finally here," he was quoted as saying by Gazzetta dello Sport. "The negotiations went on a bit too long, but I'm finally a Roma player."
Strootman becomes Roma's fourth signing of the summer so far, following Maicon, Mehdi Benatia and Tin Jedvaj to Stadio Olimpico.
The midfielder, who has 18 senior caps for Netherlands, made a total of 88 appearances for PSV after joining from fellow Eredivisie outfit Utrecht in 2011.