Eldo Kim, 20, was released on $100,000 bond into the custody of his sister, who lives in Massachusetts, and an uncle from North Carolina. Attorneys did not say where he will stay.
The U.S. attorney's office in Boston alleges Kim sent hoax emails Monday saying shrapnel bombs would go off soon in two of four buildings on Harvard's Cambridge, Massachusetts, campus. The emails came minutes before he was to take a final exam in one of the buildings.
The buildings were shut down for hours before investigators determined there were no explosives.
Federal public defender Ian Gold says Kim was dealing with finals and the third anniversary of his father's death, which is this month.
Kim, wearing a gray T-shirt and Harvard sweatpants, appeared somber as he stood before the judge.
Under the conditions of his release, he cannot enter Harvard's campus without prior approval of both the school and the federal court.
Harvard said it was saddened by the allegations but would have no further comment on the investigation.
Authorities said Kim told them he emailed the bomb threats about a half-hour before he was scheduled to take a final in Emerson Hall. He said he was there at 9 a.m. when he heard the alarm sound and knew his plan had worked, according to an FBI affidavit.
Kim became a naturalized U.S. citizen in fifth grade and renounced his South Korean citizenship, Gold said. Kim attended high school in Mukilteo, Washington. A cached version of his LinkedIn profile, which has been taken down, indicates that he did several internships in South Korea. When he was in high school he volunteered at a monastery in Nepal, according to a testimonial he wrote on the volunteer organization's website.
Gold said Kim's mother lives in South Korea.
According to the complaint, Kim sent emails to Harvard police, two university officials and the president of the Harvard Crimson newspaper, saying bombs had been placed around campus.
An FBI affidavit says Harvard determined Kim had accessed TOR, a free product that assigns a temporary anonymous Internet protocol address, using the university's wireless network.
The maximum penalties for a bomb hoax are five years in prison and a $250,000 fine, prosecutors said.