Summer signing Christian Benteke is attracting interest from several Barclays Premier League teams while fellow striker Andreas Weimann has only 18 months left of his current deal.
Rioch, who made over 150 appearances for Villa from 1969 to 1974, hopes his old club do not suffer another exodus of leading players as has happened with the likes of Ashley Young, Gareth Barry, James Milner and Stewart Downing.
He told the Birmingham Mail: "Villa have lost so many good players in recent years. I hope that is not the case again this summer.
"I would say tie them up quickly for the long term and get enough points to stay up.
"Bill Shankly told me you should never let players get into the last two years of their contract if you want them at the club a long time."