The Gunners face off against the Greek side as they hope to go deep into the competition.
The round of 16 first leg clash takes place on Thursday night in Greece.
And Arteta knows Olympiacos are dangerous opponents.
He told a press conference: "I would say that collectively it's a team that seems very alive.
"They have a very clear idea of what they want to do, they don't really play in relation to the opponent.
"They have very clear principles of how they want to play and they try to execute them against any opponent, whether they are a big club in Europe or a smaller team in the domestic league. That's what I like the most.
"Obviously they have some individual qualities that we are going to be really aware of, but I've been highly impressed with the level of the collective function of the team."