All 12 under secretaries and 14 political assistants have sworn allegiance to the SAR and the Basic Law, setting the stage for the city's 180,000 civil servants to follow suit.
The oath-taking ceremony was held at the Central Government Offices on Wednesday and witnessed by Chief Executive Carrie Lam.
The officials sang the national anthem and read out the oath, holding up their right hand.
In a statement, a government spokesman said by taking the oath, the officials "made a solemn promise on their responsibilities, genuinely showing to the community their loyalty and commitment to the Basic Law and the HKSAR and thereby boosting the confidence of the public in the politically appointed officials."
On Friday, permanent secretaries and department heads will be the next batch of officials to take the oath.
All civil servants who joined the government after July 1 are required to take an oath or sign a declaration as one of the conditions for appointment, and arrangements are also being made for all serving civil servants to swear allegiance to the SAR and the Basic Law. The Secretary for Civil Service, Patrick Nip, has said those who fail to do so risk losing their jobs.