Seventeen of the 30 counts he faced carried the death penalty, and the guilty verdict means he next faces a death penalty trial.
The jury returned the verdicts after 11 hours of deliberation over the course of two days.
Jury has reached a verdict in Tsarnaev case— U.S. Attorney MA (@DMAnews1) April 8, 2015
Tsarnaev was on trial for killing three people -- Krystale Campbell, 29, Martin Richard, 8, and Lingzi Lu, 23 -- in the bombing and shooting MIT Police Officer Sean Collier afterward.
Police say Tamerlan Tsarnaev, 26, and his brother Dzhokhar Tsarnaev, now 21, both of Cambridge, Mass., planted bombs that also injured 170 during the Boston Marathon on April 15, 2013. Tamerlan was killed by police on April 18, 2013, and Dzhokhar was captured later after a standoff in which he was seriously injured.
Collier's family applauded the verdict.
"While today's verdict can never bring Sean back, we are thankful that Dzhokar Tsarnaev will be held accountable for the evil that he brought to so many families,'' the family said. "We want to say how much we care for the victims and survivors of this senseless tragedy and their families. The strength and bond that everyone has shown during these last two years proves that if these terrorists thought that they would somehow strike fear in the hearts of people, they monumentally failed. We know Sean would be very proud of that.''
Boston Mayor Martin J. Walsh said he's thankful the first phase of the trial is over and hopes for a swift sentencing.
"I hope today's verdict provides a small amount of closure for the survivors, families, and all impacted by the violent and tragic events surrounding the 2013 Boston Marathon. The incidents of those days have forever left a mark on our city. As we remember those who lost so much, we reflect on how tragedy revealed our deepest values, and the best of who we are as a community," Walsh said.