Billy McKay has agreed a new two-year deal with Inverness, but defender Thomas Piermayr intends to move to Germany.
The 23-year-old striker who has represented Northern Ireland Under-21s, joined Caley last summer after two years with Northampton.
Manager Terry Butcher told the club's official website: "Billy has agreed to extend his contract for a period of two years.
"We're delighted he has pledged his future to us. He showed good promise in his first SPL season and we think his best is yet to come."
But former Austrian Under-21 international Piermayr has turned down a new deal.
"Thomas has indicated that he wants to play his football in Germany so we wish him all the best," said Butcher.