Kayyalathu Thomas Chacko (born 29 October 1947) is a retired Indian Administrative Service officer who held several public offices in the Government of India.

He is widely known for his commitment to increasing India's participation and role in the global economy.

Chacko was born on October 29, 1947, to the Kayyalathu house, a Syrian Orthodox Christian family, the youngest of four children, in Kottayam District, Kerala.

He then went to study at John F. Kennedy School of Government Harvard University on Edward S. Mason Fellowship where he earned a master's degree in public administration (Class of 1984).

As an officer of the Indian Administrative Service he served for over 33 years in executive, secretarial and Policy making assignments.