The fine, imposed Wednesday, was the highest ever by the exchange. It represents the latest action calling for better controls at Japan's biggest brokerage.
Nomura Chief Executive Kenichi Watanabe resigned earlier this year to take responsibility for the scandal in which information was leaked ahead of securities offerings.
Nomura has acknowledged that some employees were involved and has promised to take steps to prevent recurrences, such as reviewing internal rules and practices.
Under Japanese law, leaking inside information is not penalized as heavily as profiting from insider trading, although some are advocating the law be revised.