The Hospital Authority (HA) on Monday said a 22-month-old infected with Covid had died.
The girl developed symptoms last Wednesday and was admitted to the intensive care unit at Eastern Hospital.
The HA said her condition continued to worsen and she died on Monday afternoon, adding that the coroner's court would look into the death.
A Chief Manager of the HA, Lau Ka-hin, expressed his sympathies to the girl's family and said the authority would offer necessary support and assistance to them.
Lau said another six patients with Covid had also died. They were aged between 52 and 84.
This came as Hong Kong reported 4,019 new local coronavirus cases and 235 imported infections.
Lau noted that one of the new patients is a boy who is almost three years old.
He developed a fever on Friday and later started having spasms. The boy is in a stable condition in intensive care.
Lau appealed to parents to get their children vaccinated against Covid-19.
General Covid-19 situation: https://www.coronavirus.gov.hk/eng/
Community Clinics for Covid-19 patients: https://bit.ly/3a4BZFE
RAT reporting platform: https://www.chp.gov.hk/ratp/
Vaccination programme: https://www.covidvaccine.gov.hk/sen/
Vaccination pass scheme: https://www.coronavirus.gov.hk/eng/vaccine-pass.html
Hotline for Covid-positive patients: 1836 115