Purushothaman, who will join Tata Sons with effect from September 1, comes from Everstone Capital, where she was leading the research function.
"In her role, Purushothaman will drive macroeconomic research as well as all policy and advocacy initiatives as relevant to the businesses of the Tata group," Tata Sons said in a statement.
A graduate from the Yale University with a post-graduate degree from the London School of Economics, she has previously worked with Goldman Sachs International as Vice-President and Global Economist.
Tata Sons Executive Chairman N Chandrasekaran said, "Roopa's deep knowledge on economic matters and trends, public policy and advocacy will be extremely valuable. Her passion and engagement in the social sector will help her widely contribute to the community initiative."
Purushothaman said: "The Tata group is a one-of-a-kind institution that plays a pivotal and multi-faceted role in India's economic development. To be part of this group, during this period in India's growth story, is truly a unique opportunity.