Ja Morant's MVP-like performance on the court this year has the NBA suspicious ... 'cause the league is drug testing the Grizzlies star for the 7th time this season!!!
The 23-year-old guard could only laugh on social media ... explaining he was about to get tested AGAIN.
"Been drug tested like 6 times this season," NBA All-Star said on Twitter.
"Walked in the arena & found out I got another one today ud83dude02ud83dude44"
Of course, Morant's been playing at an incredible level -- averaging 27.