Harvey, 31, says the Roos' current ladder position of 13th - and the fact they're two games behind the three teams fighting for eighth spot - will make it hard for them to play into September for a third straight season.
However, he said much could still be gained from the rest of the year, with caretaker coach Darren Crocker keen to see improvement from the players.
"I think it's going to be tough for us to make the finals," Harvey said the day after the Roos' 22-point loss to the Western Bulldogs.
"We go into every single game thinking we can win. There's nine games to go, so we'd like to think we can win nine games.
"If we win nine games, we'll play in the finals, but [Crocker's] vision isn't based on the finals.
"It's about improving this group, and I think we took a big step forward yesterday."
He agreed the Kangaroos were already looking ahead to 2010, but said that wouldn't detract from a focus on individual development.
"We'll plan and prepare to win every single game, and if we get seven or eight out of nine, or four or five out of nine, I'm not too sure how it's going to work [with finals]," he said.
"Just as long as the group improves, 'Crock' will be very happy."
North Melbourne travels to the Harbour City to face the Sydney Swans on Sunday at the SCG.
