WASHINGTON—Top executives from the biggest U.S. banks, concerned about anti-Wall Street rhetoric already bubbling up on the 2016 campaign trail, are working to push back against the prevailing narrative that banks are bad.

Senior executives from seven of the biggest U.S. banks gathered or dialed into a March 31 meeting on the 51st floor of the Bank of America Tower in New York to discuss the upcoming election cycle and how the firms can counteract what they view as false and damaging statements about large banks, according...