He died at the Kenyatta National Hospital in Nairobi where he was admitted since March 30, officials said.
This increases to more than 10, the number of those who have died in the protests. They were shot by police who responded to the protests which they termed as illegal.
Doctors at KNH said Jamleck Mwanza died from a brain hemorrhage due to the head injuries he sustained on Thursday, March 30.
A postmortem is expected to be conducted on the body to reveal the cause of the death.
Mwanza’s parents said after looking for their son for days, they found him at KNH on Saturday, April 1.
Three of the victims including a minor were killed in Kibera, one in Tassia, two in Jacaranda, three in Kisumu, and one in Migori.
The victims include a police officer who was run over by a vehicle in Kisumu as he ran away from a charging mob.
Dozens of others are nursing wounds in hospital.
Azimio La Umoja leaders last week visited some of the victims in hospitals in the city.
The protests were called to denounce the high cost of living, electoral malpractices, and graft among other issues.