The Arsenal midfielder’s subdued display was met with jeers by a section of supporters, including when he was replaced by Lukas Podolski after 63 minutes during the 2-2 draw in Monchengladbach.
Ozil got the same treatment back in March during die Mannschaft's 1-0 win over Chile, the night he received his German Footballer of the Year award.
"I do not understand, I cannot understand," Boateng told reporters.
"In that case people should not come to the stadium. That they whistle so early into the game... I do not understand."
The final three months of Ozil’s debut season at Arsenal were disrupted by a hamstring injury and Joachim Low admits the 25-year-old is still short of fitness ahead of the World Cup.
“Ozil didn’t have one of his better days and he needs two weeks more,” the Germany coach said after the draw against Cameroon. “But after that we will see a strong Ozil at the World Cup.”
Germany meet Portugal in their opening Group G fixture on June 16.