Modi has undertaken similar walks earlier too. He broke his security cover after last year's Independence Day speech at the Red Fort when he stepped out of his car to meet school children.
Donning a yellow orange headgear with a red tail and kurta pajama and Nehru jacket, Modi waved to the crowds enthusiastically as he zig-zagged the Rajpath, closely followed by security personnel and his slow-moving motorcade.
The Prime Minister started his walk soon after President Ram Nath Kovind and his South African counterpart and chief guest at the Republic Day parade, Cyril Ramaphosa, left Rajpath.
The crowds appeared pleased to get a glimpses of the Prime Minister from close.
As Modi went close to the seating enclosures, some chanted "Modi, Modi" while others captured the moment on their mobile phones and cameras.
Many came near the makeshift barricades to greet him.