The case was confirmed following a test by the Chinese Center for Disease Control and Prevention early on Saturday.
The child is being treated at the Beijing Ditan Hospital, and is in stable condition, Zhong Dongbo, deputy director of the Beijing Municipal Health Bureau, said in a press briefing.
The girl developed flu symptoms, including fever, cough, sore throat and headache, Thursday morning. She was brought to the Beijing Ditan Hospital to seek medical treatment around noon and was then hospitalized for lung infection.
The child received the drug Tamiflu as well as intravenous drips on Thursday night and later was transferred to an intensive care unit after condition worsened. After an oxygen therapy and other treatment, her suffocation and coughing symptoms eased markedly and body temperature fell to 37 degrees Celsius from 40.2 degrees Celsius, a spokesman with the Beijing Ditan Hospital said.
Two people who have had close contact with the child have not shown any flu symptoms, a spokesman said. He added that the girl's parents were engaged in live poultry trading in a township of Shunyi District in Beijing's northeastern suburbs.
The new case raised the number of H7N9 infections in China to 44, with all the other 43 in the eastern parts of the country. The first known human infections have claimed the lives of 11 people, according to the National Health and Family Planning Commission.
