Chui Sai was born in 1957, Macau. He graduated from Lingnan Middle School, studied abroad in the United States. He obtained a BA in health management at California State University and an MA and PhD in public health from Oklahoma State University.
Before the return of Macao to China, Chui Sai was principal of Jingping School and Jingping Professional Development Center. He also joined a number of social service organizations in Macao. He served as a member of the Legislative Council of Macao, and of the Selection Committee for the first government of Macao SAR. After the establishment of the Macao Special Administrative Region, Chui Sai served as Secretary of the Social Affairs and Culture Department as well as in other positions. He is member of first session of the Executive Council of the Macau SAR Government.
In August 2009, he became the third Chief Executive of the Macao Special Administrative Region. Chief Executive and in August 2014 he was re-elected as the fourth Chief Executive of the Macao Special Administrative Region. He served as Chief Executive of the Macao SAR until 2019.