Wallace, 61, is the brother of NASCAR Hall of Famer Rusty Wallace.
He most recently competed in three NASCAR Xfinity Series races this year at the Indianapolis Road Course, Road America and the Daytona Road Course.
Wallace has started over 800 races among NASCAR's three national divisions, winning five Truck races and four Xfinity races.
A social media post from Wallace violated this section of NASCAR's behavioral policy:
“Public statement and/or communication that criticizes, ridicules, or otherwise disparages another person based upon that person’s race, color, creed, national origin, gender, sexual orientation, marital status, religion, age, or handicapping condition.”
In order to be reinstated, Wallace must first complete sensitivity training.