Seeded 10th, Sindhu, who won the Malaysia Grand Prix in May this year, had to sweat it out for one hour and 11 minutes to prevail over unseeded Imabeppu 21-19 19-21 21-17.
World number 12 P V Sindhu, who made her debut at the World Championship, had beaten the world number 32 Japanese in Japan Open last year.
Sindhu, who got a bye in the first round, will have to raise her game by leaps and bounds as he takes on the winner of the match between second seed Wang Yihan of China and Indonesian Belaetrix Manuputi in the next round.
Sindhu's higher-rated compatriot, Saina Nehwal will open her campaign against Olga Golovanova of Russia.
Saina, seeded third, had got a bye in the opening round. However, it was heartbreak for India in the men's doubles competition as Tarun Kona and Arun Vishnu crashed out in the second round, but not before giving a tough fight to the fancied Indonesian pair of Alvent Yulianto Chandra and Markis Kido.
The unseeded Indian duo fought tooth and nail for 40 minutes before going down 15-21 21-13 17-21 to the Indonesian pair, who are seeded 15th in the competition.
Kona and Vishnu had earlier got a walkover in the first round after Polish pair of Adam Cwalina and Przemyslaw Wacha conceded the encounter. India's hopes in the men's doubles event now rest on Pranaav Jerry Chopra and Akshay Dewalkar who will play the German duo of Peter Kaesbauer and Josche Zurwonne in their opening match later in the day.
In the mens' singles event, Ajay Jayaram will be up against Pablo Abian of Spain in the second round, 13th seed Parupalli Kashyap will take on Czech Republic's Petr Koukal.