The Buddies captain has not featured since the 1-0 defeat by St Johnstone on February 23 with a calf injury sidelining him for the last three weeks.
But Goodwin came through a training session yesterday and, with Lee Mair's stomach muscle injury meaning he misses out, Lennon admits that Goody's presence is vital on Sunday.
The St Mirren manager said: "Jim is our leader and a huge presence for us on the pitch. So it was a huge plus that he came back to training yesterday. We will monitor him closely over the next few days but hopefully he will be ready to lead the boys out.
"The great thing about Jim is that he is a great communicator. When you have matches like a cup final, you need your captain organising the side and making sure that everyone is being encouraged and knows what they is doing.
"On top of that, Jim is a real winner and I know how much it will mean to him to lead the side out on Sunday and that he will absolutely put everything on the line to help us win the trophy."
The Buddies boss has no doubt that his side's trip to St Andrews, where they are based for the build-up, has been a smart move.
Lennon said: "It has been great to get away and just focus on the final. What we needed is the best possible preparation to give ourselves the best possible chance of a victory.
"I am confident we have that at St Andrews University."
Lennon was tight-lipped over the prospects of Estonian trialist Sander Puri earning a new deal and a shock place in Sunday's 16-man squad.
He said: "Sander has made a good impression but we will make our decision at the end of the week."