Leonard Fournette just did his best 'Price Is Right' impression with his mom ... 'cause she just got A NEW CAR!!!!!

Fournette -- who was taken 4th in the NFL Draft by the Jaguars -- is projected to sign a $27 million contract with an $18 million signing bonus. 

So, with all that dough coming in, the former LSU superstar decided to spread the wealth by gifting his mother with what appears to be a brand new Mercedes Benz GLE Coupe (which start at $110k). 

Leonard is the latest 1st round pick to hook his mom up with a sweet ride -- Deshaun Watson bought his mother a new Jag.