The 17-year-old lasted just 11 minutes of the second string's 2-0 win over Torquay on Tuesday before being substituted after a tackle with Gulls defender Angus McDonald.
Harvey left Home Park on crutches as a precaution but it is hoped he could be available for the Pilgrims' vital clash with Aldershot this weekend.
"Tyler had an impact injury to the side of his knee," Argyle coach Kevin Nancekivell told the Plymouth Herald.
"I have spoken to Paul (Atkinson) the physio, and he's hopeful that it's not too serious. Tyler is on crutches but only as a precaution.
"Fingers crossed he could be available for Saturday. We will wait and see what develops over the next 24 hours."