Marseille were due to host Saint-Étienne at the Stade Vélodrome on Friday to begin the 2020-21 football season.
The club had confirmed on Tuesday that three new players had tested positive for COVID-19, bringing the total number of affected players at Marseille to four.
The Professional Football League (LFP) announced at midday that Marseille's fixture had been postponed in light of the medical results.
"The national COVID commission indicates to the LFP Competitions Commission that the virus is circulating within the Marseille club," said the LFP in a statement.
The match has been rearranged to the 16 or 17 September, subject to changes in health conditions.
Marseille have not confirmed which players have tested positive, although defender Jordan Amavi is believed to be Thursday's positive case
Amavi had re-posted a message of support from teammate Dimitri Payet on Twitter on Saturday.
Meanwhile, on Friday, French club Nîmes also cancelled a friendly fixture against Dijon as a safety measure after a suspected case of COVID-19. Nîmes are due to host Brest on Sunday for their first fixture of the 2020-21 Ligue 1 season.
A total of 40 players from 11 Ligue 1 clubs have tested positive for COVID-19 in recent weeks, according to AFP.
According to the medical protocol of the League, the national "COVID commission" can postpone fixtures when three or more members of the same club have tested positive for coronavirus.
The latest news is a tough blow for French football and raises questions about the smooth running of the professional sport following the pandemic.
Top-flight football in the country was suspended in March, but unlike other leagues around Europe, France decided to end the Ligue 1 season early, rather than restarting - a move criticised by several clubs.
The setback also comes as two French clubs - Paris Saint-Germain and Lyon - are preparing for UEFA Champions League semifinals in Lisbon. It is the first time ever that France has had two teams at that stage of the competition.
The 2020-21 Ligue 1 season will now begin on Saturday, with Bordeaux facing Nantes. Because of the health crisis, a maximum capacity of 5,000 spectators is allowed in French stadiums.
Other leagues in England, Italy, Germany and Spain are expected to begin the 2020-21 campaign in September.