The decision on the unsecured overnight call money comes amid concerns of a recession in the United States and a global credit crunch, which could impact Japan's recovery.
The bank said the decision was unanimous among all seven members of its policy board, Kyodo news service reported. The rate has been in effect since last February.
BOJ has been without a governor for the past three weeks but Wednesday parliament cleared the way for Masaaki Shirakawa to take the job, the report said.
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