He praised the striker following his arrival from United earlier in August and said there is more still to come:
On his transfer fee, he added to Sky Sport Italia (h/t Football-Italia), "Let's not forget Lukaku cost €65 million to be paid over five years, so when people talk about big money spent, it wasn't even that much."
BBC Sport's Simon Stone reported his transfer fee could rise to a club-record €80 million (£74 million), so it seems Conte's figure of €65 million (£59 million) is before add-ons.
Given the Red Devils spent an initial £75 million to sign him from Everton in 2017, in a deal that included a potential £15 million in add-ons, it's clear they've been unable to recoup all the money spent on the Belgian.
Lukaku found the net on Monday when he finished a rebound from Lautaro Martinez:
He's no stranger to a debut goal, and he also showed another side to his game as he brought his team-mates into play:
The Independent's Jack Rathborn was impressed with his performance:
The striker only scored 15 goals in 45 appearances last season, but he netted 27 in his first campaign with United.
He has been one of Europe's most prolific strikers in recent years, with his goal against Lecce being the 236th strike of his career for club and country.
Conte won three consecutive Serie A titles with Juventus and guided Chelsea to the Premier League title in his first season at Stamford Bridge. He's a manager who can often coax a great deal from his players, so he could be the ideal coach to get Lukaku firing again after he disappointed with United last season.
If the Italian can get the best out of Lukaku, they'll have an enormous asset on their hands.