Uniformed officers staged a small rally Wednesday at a fan area in central Athens where supporters of AC Milan and Liverpool gathered before the game at the city's Olympic Stadium.
They also handed out leaflets in English and Italian to fans arriving at Athens International Airport and hung a protest banner from the side of a foot bridge next to the Public Order Ministry.
The peaceful rally took place amid massive security for the final, with 8,500 officers patrolling Athens and a further 6,500 in a support role.
Police protest leader Dimitris Kyriazidis said his union would not give up its right to demonstrate for fellow officers, whose starting salary can be around Ђ600 (US$800) a month.
"This will not have any negative effect on the country or the final. I cannot understand why people portray it this way," Kyriazidis said.
He said off duty police had secured 200 tickets for the final and were considering whether to unfurl a protest banner inside the stadium.
"We demonstrate that we have the experience and know-how to host such a major event ... this is everyone's responsibility, above any personal interest," Karamanlis said.