Strootman, who has previously been strongly linked with a move to Manchester United, has expressed a wish to leave PSV after claiming several clubs are interested.
Reports in Italy have suggested that Roma are closing in on a deal to sign the 23-year-old for a fee of €17million (£14.6m), which could eventually rise to €20m (£17.2m).
However, after selling Erik Pieters, Dries Mertens and Jeremain Lens already this summer, PSV's technical director Marcel Brands does not want to lose another key player, unless a big offer is made for Strootman.
"Roma have contacted us to tell us that they are interested in Kevin Strootman," Brands told Fox Sports.
"We have told Roma that Strootman is not for sale, and only an important offer could convince us otherwise.
"In our opinion, Roma is the only club to be interested in Strootman, but they have made no offer."
Strootman's agent Chiel Dekker is waiting to see if the clubs can come to an agreement before opening any talks about a move to Serie A.
Dekker told De Telegraaf: "We are aware of the interest and the communication between PSV and Roma, but we will only come into action when Marcel Brands gives the signal that both clubs have come to an agreement."