Nooyi earned a bachelor's degree in chemistry from Madras Christian College in 1976 and a master's degree in business administration from the Indian Institute of Management in Calcutta two years later. After moving to the United States, she received an additional master's degree in public and private management from the Yale School of Management in 1980. For the next six years, Nooyi worked as a consultant for the Boston Consulting Group. She later held executive positions at Motorola, Inc., and the engineering firm Asea Brown Boveri (now ABB).

In 1994 Nooyi joined PepsiCo as senior vice president of corporate strategy and development. In 2001 she was named president and chief financial officer of the company. Nooyi was responsible for guiding a major restructuring, which included the company's spin-off of its restaurants—which included KFC, Pizza Hut, and Taco Bell—into TRICON Global Restaurants (which later became YUM! Brands, Inc.), as well as the spin-off of PepsiCo's bottling operations. In addition, she oversaw the acquisition (1998) of Tropicana Products and a merger in 2001 with the Quaker Oats Co. (Quaker Foods and Beverages) as part of the company's strategy of diversifying into more healthful drinks and foods.

Nooyi assumed the title of CEO in October 2006 and the next year became chairman of the board as well. The fifth chairman and CEO in PepsiCo's 42-year history, Nooyi was the first woman to lead the soft-drink and snack-food giant and one of only 11 female chief executives of Fortune 500 companies. Although analysts expressed surprise at the timing of Nooyi's appointment as chairman (her predecessor, Steven Reinemund, had served just five years before abruptly deciding to retire), many praised the skills that she would bring to the job. Nooyi was expected to continue the strategy of making PepsiCo a well-balanced consumer-products company that would be less reliant on sales of its flagship soft drinks and to aggressively pursue international expansion. She also expressed a particular desire to help make more nutritional foods available in less-developed countries.