The 27-year-old left-back has signed a three-and-a-half year contract with the Championship club.
Derby have moved to bring in a new left-back due to long-term injuries to Craig Forsyth and Max Lowe.
Head Coach Paul Clement told the club’s official website: “We’re delighted to welcome Marcus Olsson on board; he strengthens the options for us at left-back.
“He is a player that we have been monitoring for some time and I am very pleased that we have now completed the deal.
“Stephen Warnock has done fantastically for us in the last few months but we felt it was important to have another specialist in that position in the squad, as well as being at a perfect age to develop with us.
“Craig Forsyth and Max Lowe are both going to miss the rest of the season due to injury, so we felt it was important to avoid any issues further down the line.
“Marcus was Blackburn’s Player of the Season last year so that shows how highly rated he was there and Craig Short, who I know well, has provided a glowing reference after working with him at Ewood Park.”
SIGNING: #DCFC have completed the signing of left-back Marcus Olsson from @OneRovers: https://t.co/ayfHr8o0dS pic.twitter.com/HgwGmUvmGf
— Derby County (@dcfcofficial) January 26, 2016
