Villa, who lost to Manchester United in the final of the competition last season, take on their bitter rivals at St Andrew's on Wednesday night.
"We must remain extremely focused on the football side," Houllier said. "One of the key weapons in games like this is your composure and your control. That goes for both teams.
"In football, we know that provocation is never punished, it's always retaliation which is punished. We have to make sure that if we are being provoked, we've got the nerve to stand up to the situation and not react."
The Frenchman also claimed both sets of fans had a responsibility to ensure the game passes without incident off the pitch.
"I hope it remains a game of football," he said. "I have heard so many things about the fact that the fans could be heated and that there would be problems. I can only control the team, I can't control the fans. I hope they can control themselves."