Poetry editors Timothy Donnelly, Barbara Fischer and Stefania Heim said on Twitter last week they're "dismayed" and are stepping down July 1.
Editors-in-chief Deborah Chasman and Joshua Cohen announced earlier that they concluded the allegations against Díaz didn't rise to the "severity that animated the #MeToo movement."
Author Zinzi Clemmons and other female writers have recently shared stories of abusive behavior by Díaz, who has said he takes responsibility for his past.
Chasman said Monday no other editors have resigned. She and Cohen told Publishers Weekly they were sad about the departures but stood by their decision. Díaz has been the publication's fiction editor since 2003.