Mistry considers himself to be of Irish nationality as his mother is Irish by birth, although his father is Indian-born. Mistry is married to Rohiqa Chagla and has two sons.
Cyrus Mistry is the youngest son of Pallonji Mistry, an Irish-Parsi construction tycoon. In the 1930s, Mistry's grandfather first bought shares in Tata Sons, which as of November 2011, stood at 18.5 percent, making him the largest single shareholder in a firm.
Cyrus P. Mistry completed his schooling from the Cathedral and John Connon School in Mumbai. Later, he graduated from the Imperial College, London with a Bachelor’s degree in Civil engineering, followed by a Master of Science in management from the London Business School. He is also a fellow of the Institution of Civil Engineers.
At the age of 23, Cyrus Mistry joined the board of his family’s engineering company Shapoorji Pallonji and Company, which is part of the Shapoorji Pallonji Group. Three years later he became the managing director of the same. From 24th September 1990 to 26th October 2009 he was Director of Tata Elxsi Limited. Until September 2006, he served as Director of Tata Power Co. Ltd. On 1st September 2006, he joined the board of Tata Sons.
On 28th December 2012, Cyrus Mistry was appointed as the chairman of Tata Sons, taking over the reins from Ratan Tata. This is the second time in the company's 143-year old history that a non-Tata will head the group; Sir Nowroji Saklatwala had led the group between 1932 and 1938. In addition, he is also chairman of all major Tata companies including Tata Steel, Tata Motors, Tata Consultancy Services, Tata Chemicals, Tata Teleservices, Tata Power, Tata Industries, Tata Global Beverages and Indian Hotels.