The April 15 tribute will be hosted jointly by Boston Mayor Martin Walsh and Gov. Deval Patrick in coordination with One Fund Boston, the charity set up to help victims, the Boston Athletic Association said.
The 118th running of the Boston Marathon is set for April 21.
"On April 15, we recall the courage, compassion, and commitment of our great city and its people," Walsh said in a statement.
Dzhokhar Tsarnaev has pleaded not guilty to 30 federal counts, including using a weapon of mass destruction. He faces the death penalty at trial, scheduled to start November 3.