Dias Kadyrbayev, 20, is accused of removing a backpack containing emptied-out fireworks from Tsarnaev's dorm room after realizing he was suspected of carrying out the 2013 attack with his brother, Tamerlan Tsarnaev.
Kadyrbayev was scheduled to go on trial next month on obstruction of justice and conspiracy charges.
Prosecutors said Kadyrbayev and another friend, Azamat Tazhayakov, decided to take the items from Tsarnaev's room at the University of Massachusetts-Dartmouth several days after two bombs exploded near the finish line of the marathon, killing three people and injuring more than 260. The items, along with Tsarnaev's laptop computer, were removed hours after the FBI publicly released photographs of Tsarnaev and his brother as suspects in the bombing.
Tazhayakov was convicted last month of agreeing with the plan to remove the items.
During Tazhayakov's trial, witnesses said Kadyrbayev took the backpack and threw it in the trash.
Prosecutors said the items were removed from Tsarnaev's room hours after Kadyrbayev received a text message from Tsarnaev saying he could go to his dorm room and "take what's there."
The backpack and fireworks were recovered later in a New Bedford landfill. Prosecutors said the fireworks had been emptied of explosive powder that can be used to make bombs.
Tamerlan Tsarnaev was killed in a shootout with police several days after the bombings. Dzhokhar Tsarnaev has pleaded not guilty to 30 federal charges and faces the possibility of the death penalty if convicted. His trial is scheduled to begin in November.
A third college friend, Robel Phillipos, of Cambridge, is charged with lying to federal investigators. He is scheduled to go on trial next month.