The eighth-seeded Kashyap, who is a Commonwealth Games bronze-medallist, staved off the stiff challenge posed by Gao with a 21-13 14-21 21-19 win that came after an hour and 18 minutes of slogging.
Kashyap will now face compatriot R M V Gurusaiutt, who endured an equally tough fight against Malaysia's Muhammad Hafiz Hashim before winning 21-18 19-21 21-13 in exactly an hour.
Ajay Jayaram scored an upset win when he got the better of third-seeded Japanese Kenichi Tago 21-13 21-17 to set up a second-round clash with Singapore's Zi Liang Derek Wong.
Sourabh Verma also made his way into the next round after rallying to beat Malaysia's Daren Liew 9-21 21-17 21-12 in a match lasting a little over an hour.
The lone Indian in fray in women's singles, P V Sindhu too made a fine start as she sailed past American Jamie Subandhi 21-15 21-12.
Sindhu has a tough match at hand as she would be facing eighth-seeded Thai Porntip Buranaprasertsuk in the second round.
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Among the Indians who disappointed was Anand Pawar as he lost 17-21 12-21 to second-seeded Chinese Jin Chen in 43 minutes.
The Indians faired badly in the doubles competition with the combination of Tarun Kona and Arun Vishnu letting slip the early advantage to lose 21-18 12-21 19-21 to the Danish pair of Rasmus Bonde and Mads Conrad-Petersen in under an hour's time in the men's doubles opening round.
In the same event, Pranaav Jerry Chopra and Akshay Dewalkar lost 11-21 21-17 18-21 to the Thai team of Patiphat Chalardchaleam and Nipitphon Puangpuapech in 52 minutes.