"Members of this racket had tricked around 360,000 people in Germany into participating in non-existent lottery draws for a monthly fee of €29.90," the police said in a statement.
"Their profit exceeded €36.5 million."
The racket used phone lists illegally obtained from betting companies. It employed phone operators who offered cash rewards, cars and free trips to lure victims.
Bogus companies had been set up to funnel the proceeds into various bank accounts.
The two men arrested in Athens had been senior operatives in the racket from 2009 to 2012, police said.