Spurs were 2-1 down doing into the fifth-minute of injury time at the King Power Stadium before Bergwijn scored two goals in 79 seconds to give them the unlikeliest of 3-2 wins.
Bergwijn has been linked with a move to Ajax, with the Eredivisie giants reportedly already submitting a bid for the 24-year-old.
However, Conte says the player is happy at Tottenham, and he has absolutely no intention to sell him.
"In the past when someone asks me about Steven Bergwijn I was very clear," Conte said.
"I said that for me he is an important player because he has characteristics that in our squad we don't have many creative players.
"He is very good in one vs one, good to beat the man. He can play striker, he can play number 10 and for us, for me, he is an important player and we have to try to improve, to become stronger, not to lose a player and become less strong.
"Steven is a player that if he's in good physical condition and he has good fitness he can start the games or he can come on and change the game.
"For me I think he's an important player and you know very well the player has to be happy and I think the player is happy to stay with us and play for Tottenham."
On the match itself, Conte added: "I think it was an amazing game.
"Honestly, we didn't deserve to lose the game and also we didn't deserve to draw because we created many chances and in many circumstances we were unlucky.
"To arrive in added time losing 2-1 was honestly a great, great disappointment. At the end my players showed great resilience, great desire. Don't give up. This must be our philosophy, don't give up and fight until the end.
"They showed me great desire. When we had equalised, we got the ball and we wanted to restart the game and to try to win. I think it was good for me to see this type of attitude from my players."