The 18-year-old sprinter scripted history by becoming the first Indian woman athlete to win a gold at the world level. She clocked 51.46s to win the gold.
Modi said he was "extremely moved" seeing Hima passionately searching for the Tricolour immediately after winning the 400m race.
"Unforgettable moments from @HimaDas8’s victory. Seeing her passionately search for the Tricolour immediately after winning and getting emotional while singing the National Anthem touched me deeply. I was extremely moved. Which Indian won’t have tears of joy seeing this!, the prime minister said on Twitter.
No woman before Das has won a gold medal in a World Championship at any level, be it youth, junior or senior.
She is also the first Indian to have won a gold in a track event at the world level.
Das hails from Dhing village in Assam's Nagaon district.