Benzema was indefinitely suspended from the France team in December after being placed under investigation over an attempt to blackmail international team-mate Mathieu Valbuena for a sex-tape.
However, Griezmann has backed Benzema to respond on the park, but said France still have the talent to do the job without him.
"Whatever's going on with him, he always responds on the pitch," Griezmann said.
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"[But] there are other forwards, such as [Andre-Pierre] Gignac and [Olivier] Giroud, and [Anthony] Martial can also do a good job.
"We'll see what happens in the upcoming two games. Karim is an important player for us."
Griezmann, who has scored 24 goals for Atletico Madrid in all competitions this season, will be hoping to bring his club form to international level.
"It's different at international and club level. At Atletico you see the guys in the dressing room every day. Here it's different because you only have a few days to prepare for matches," the 25-year-old said.
"I try to do my best, although I haven't always produced top performances [for France]. I know that I have to work even harder."