"Congratulations @sundarpichai. My best wishes for the new role at @google," Modi tweeted after the announcement.
Communications and IT Minister Ravi Shankar Prasad too tweeted his greetings, saying: "Really proud to note that #India born @sundarpichai has been appointed as CEO of @google".
Microsoft Chairman Satya Nadella and Pichai's former colleague and SoftBank President Nikesh Arora conveyed their best wishes.
Nadella tweeted: "Congrats @sundarpichai, well deserved."
Arora, who was Pichai's colleague at Google, described the new chief as "a brilliant guy, clear thinker, gets things done and a wonderful person at that".
Arora had quit Google last year, where he was serving as the Chief Business Officer to join Japan's SoftBank Corp.
Bret Taylor, co-creator of Google Maps, ex-CTO of Facebook and co-founder of technology Quip, also congratulated Pichai.
Congratulating Pichai, industry body Nasscom said he will be "instrumental in infusing a new sense of enthusiasm and innovation in the sector globally".
"Sundar Pichai is a new-age leader and with his immense experience in the field of software products, he will be a valuable asset for Google and the industry in its next phase of evolution and growth," it said.
Pichai is a B Tech from IIT-Kharagpur, an MS from Stanford University and an MBA from the University of Pennsylvania.
