A police officer said thousands of Kashmiris defied harsh security restrictions and joined the protests after Friday Muslim prayers. He spoke on condition of anonymity because of department policy.
Clashes erupted in over a dozen places, including in the main city of Srinagar, between rock-throwing protesters and troops, who fired live ammunition, shotguns and tear gas.
Police said the man died in southern Pulwama town. At least 50 civilians were injured in the clashes.
Earlier, government forces blocked worshippers from offering prayers at large mosques for the seventh consecutive week. However, prayers were allowed at small neighborhood mosques.
A strict curfew, a series of communication blackouts and a tightening crackdown have failed to stop some of Kashmir's largest protests against Indian rule in recent years, triggered by the killing of a popular rebel commander on July 8.
Residents have struggled to cope with shortages of food, medicine and other necessities.
At least 67 civilians have been killed and thousands injured, mostly by government forces firing bullets and shotguns at rock-throwing protesters. Two policemen have also been killed and hundreds of government forces have been injured in the clashes.
Kashmir is divided between India and Pakistan and claimed by both. Most Kashmiris want an end to Indian rule and favor independence or a merger with Pakistan. More than 68,000 people have been killed since rebel groups began fighting Indian forces in 1989 and in the subsequent Indian military crackdown.