Manuel Gutierrez was apparently shot in the chest near a security barricade Thursday as protesters battled police by throwing rocks and setting fire to piles of rubbish to block traffic into Santiago, RTVE reported.
Some 600,000 were reportedly involved in protests across the country against the country's unpopular president, Sebastian Pinera.
Witnesses, friends and family have blamed police for firing the shots that killed Gutierrez, marking the first fatality in months of demonstrations across the country.
Police said water cannons and tear gas were used to defuse the riots.
An estimated 1,394 arrests have been made nationwide and 53 civilians and 153 police officers were injured.
Demonstrations for education reform started in April when thousands of students took to the streets across Chile.