The striker enjoyed a good first season at Swansea following his move from Vitesse Arnhem last summer, scoring 24 goals in all competitions including 16 in the Barclays Premier League.
Ivory Coast international Bony recently told Sky Sports of his ambitions to play for a "bigger club" and appear in the Champions League, while Monk was recently installed as the Swans' manager on a permanent basis having replaced Michael Laudrup during last season.
"I think we can hold on to him," Monk told Talksport. "He's a good guy but money talks.
"It would have to be an astronomical fee for him to leave though and we're not a selling club. We're not in any debt. We don't need to lose anyone so we're in a strong position."
Bony scored five times in Swansea's last four games as the Welsh side secured a third season in the top flight, including the final one of the campaign in the 3-1 win at Sunderland.
"He's a proper professional," Monk added. "He's not the sort of player to take it easy. Every single day he pushes himself and everyone around him. The more players you have in your squad, the better you're going to be."