Does the Apple Garden Sub-district Office in Shijingshan District of Beijing belong to a public institution?

Belong to. Sub-district offices belong to the agencies and administrative institutions of the district government, and the staff inside have the administrative establishment of civil servants. Institutions refer to social service organizations established by the government to engage in education, science and technology, culture, health and other activities by using state-owned assets, and refer to the state's purpose of social welfare.