"We're delighted to announce the signing of Clinton Njie, subject to international clearance and work permit," the club said in a statement.
The 22-year-old, who has scored six goals in 11 appearances for his country, can play centre forward or in one of the wide attacking positions and has signed a five-year contract with Spurs, who finished fifth last season.
Njie managed eight goals for Lyon in 33 appearances last term as they finished runners-up behind Paris St Germain.
Spurs, who lost 1-0 to Manchester United in their opening Premier League match of the season, only have Harry Kane as a recognised striker after selling the under-performing Roberto Soldado to Villarreal on Friday.
Togo striker Emmanuel Adebayor also looks to be on the way out of the north London club after hardly featuring in the first team during Mauricio Pochettino's first season as manager last year.
The former Arsenal, Real Madrid and Manchester City striker has not been given a squad number with Spurs, suggesting his days at White Hart Lane are numbered.
Tottenham host Stoke City later on Saturday.
(Writing by Patrick Johnston in Singapore, editing by Ed Osmond)
