Bony has scored more Premier League goals in 2014 than any other player, finding the net 18 times for the Swans.
The 25-year-old has scored six times so far this season, but Monk says the Welsh side do not have to sell the Ivorian.
"It would take an astronomical fee for Bony to go anywhere," said Monk.
"We are not a selling club, we don't need to sell.
"We are very much committed with our players and they are committed to us and that's how we move on."
Bony scored 25 goals in his first season after signing for a club-record £12m from Dutch side Vitesse Arnhem.
He scored twice for the Ivory Coast at the 2014 World Cup finals and was the subject of transfer speculation during the close season.
Arsenal, Liverpool and Tottenham were all reported to be interested in Bony, but Monk insisted the striker was not for sale.
In November, Bony signed a one-year extension to his contract with Swansea, a deal which could keep him at the Liberty Stadium until 2018.
Monk, whose side lie eighth in the Premier League, says Bony's goalscoring record in 2014 is well deserved.
"It shows that the work that we are doing with him is paying off," said Monk.
"He works very hard on his finishing and his fitness, so all credit to him and long may it continue."
Bony will be away at the 2015 Africa Cup of Nations finals in January and February.
Monk says Swansea, who host Queens Park Rangers on Tuesday in the Premier League, are looking to add to their options up front.
"With Wilfried being away for, I think it's a six or seven-game period, we'll obviously be looking to bring in cover in that position," said Monk.
In October Bony said his likely involvement in the Africa Cup of Nations would put clubs off bidding for him.
Swansea City manager Garry Monk says it will take a huge bid to prise away top scorer Wilfried Bony from the club during the January transfer window.