The competition, featuring the club champions of each continent, arouses great interest in South America, Asia and Africa, but is barely noticed in Europe amid the torrent of pre-Christmas domestic football.
"I could understand that when we played this competition in the past years in Japan or the United Arab Emirates, that there was less interest," Blatter told reporters.
"But now it is on Europe's doorstep and there is not so much interest, I agree that we are disappointed."
Blatter said he hoped the tournament, being staged in Morocco this year for the first time, would eventually be included in the international calendar to avoid clashing with European league football.
"I think there should be a little bit more attention to other competitions, but with the big leagues in Europe, you have the question of the calendar.
"They have to play every day, even if they don't play in the league, there is the FA Cup and the League Cup, every day or every other day there is football."
"The Club World Cup is not yet protected by the international calendar as the World Cup is," he said.
Blatter said he was delighted by this year's tournament, which ends on Saturday with Raja Casablanca, who qualified as champions of host nation Morocco, facing European champions Bayern Munich in the final in Marrakech.
Raja reached the final with a shock 3-1 win over South American champions Atletico Mineiro on Wednesday, stunning the roughly 10,000 fans who had made the long journey from Brazil.
"The quality of the matches we have seen, with some very good football in a remarkable ambience, this is best publicity, and the best way of getting more attention of the five big leagues," said Blatter.
"It's a question of solidarity," he added. "They should also be interested in the other leagues and have a look at what is going on elsewhere."