Yes. It is based on the beliefs that 1) races exist, and 2) that some race(s) has some superiority to other race(s). It is an attempt to equalize that difference.
However, AA policies could be (and sometimes are) applied in non racist ways. For example, they could be applied in sexist ways.
AA policies do NOT function on the notion that race is the cause of the superiority/inferiority differences. If that is your measure of racism, then you could say they aren't racist.
You used affirmative action, so I assume you are refering to US policies. Other countries usually use other names like "positive discrimination."