Gurjit Kaur was the star of the show with five goals. Lilima Minz (two), Jyoti (two), Monika, Vandana Katariya, Rajwinder Kaur and Sonika were India's other scorers.
The win marked a solid start to Janneke Schopman's tenure as India head coach. The Dutchman, who deputised for former boss Sjoerd Marijne, took over the reins after Marijne left to post the Tokyo games.
Led by goalkeeper Savita Punia in the absence of captain Rani Rampal, who guided the Indian women to a fourth-place finish at Tokyo 2020, India took control of the match against debutants Thailand from the first whistle.
Gurjit Kaur opened the scoring after converting a penalty corner two minutes in. And Vandana Katariya made it 2-0 seconds later. Three back-to-back goals by Lilima Minz, Gurjit and Jyoti saw India take a commanding 5-0 lead at the end of the first quarter.
India scored four more in the second quarter, with Rajwinder Kaur. Lilima scored one each to add to Gurjit's two from the period.
After half-time, the Thai defence put up a much stronger front but couldn't stop India from adding to the scoreline. Jyoti and Sonika scored in the third quarter while Monika got on the scoresheet in the fourth before Gurjit. She had started the rout, wrapped up the thumping with the final goal of the match.
India, the highest-ranked team in the tournament, were scheduled to play Malaysia on Monday. But the match has been called off after Malaysian player Nurul Faezah Shafiqah Khalim tested positive for COVID-19.
India will play hosts South Korea on Wednesday.