Frandsen was recently recalled to the Denmark squad for their two latest Euro 2004 qualifying games after a year away from the international arena.
“I phoned the national coach, Morten Olsen, and told him I am stopping," Frandsen told the clubs official website.
"After the last time I joined up, I decided that it would be my last time.
“I have won 24 international caps but I never really settled into things.
“I never played a full 90 minutes for Denmark.”