The Dutch defender has been out of since April because of the problem, which prevented him from being named in the Netherlands' squad for the FIFA World Cup.
Right-back Van der Wiel has now returned to training ahead of pre-season but, while the club have been pleased with his recovery, he is not deemed fit enough to join the members of the squad not involved in the World Cup in Austria.
A statement on PSG's official website read: "Defender Gregory van der Wiel will not participate in Paris Saint-Germain's training camp in Austria.
"Late last season the player suffered inflammation of the patellar tendon in his right knee.
"After six weeks of rest and treatment, a medical evaluation performed at Clairefontaine earlier this week showed a very favourable evolution of his injury.
"In order to continue his protocol and care, the Netherlands international will pursue a specific training programme away from the group for a period of fifteen days.
"Gregory van der Wiel will continue his protocol of rehabilitation , accompanied by a physiotherapist of the club, in a specialised centre."
PSG begin their pre-season preparations against Austrian side Hartberg on July 8.