The Indians, ranked 13th in the world, were trailing by two goals at half time after World No. 10 Japan scored through Emi Nishikori (15th minute) and Mie Nakashima (28th).
But the Indians made a valiant fightback as Rani Rampal (31st) and Lilima Minz (40th) scored a goal each in the third and fourth quarters to secure points for their side.
They dominated the share of possesion but failed to create clear-cut scoring opportunities in the first 30 minutes. Whatever chances India created, the strikers misfired inside the rival circle.
Japan, on the other hand, took time to settle down but got into the groove as the game progressed.
India's first scoring chance came in the seventh minute but Preeti Dubey, who was lurking in front of Japan goal, failed to get a touch to Deepika's cross. A minute later Poonam Rani shot wide from inside the circle.
In the second quarter, the Indian girls enjoyed more possession but were guilty of giving away the ball too easily.
Japan doubled their lead two minutes from half time from a swift break through Nakashima who deflected in a cross from left which India captain Sushila Chanu failed to cut off.
Down by two goals, India came out with more purpose after the change of ends and put pressure on the Japanese goal with relentless attacks.
Japan missed their second short corner, but India utilised the second of two more penalty corners they earned in the third quarter when Lilima Minz scored from a rebound to level the scores.
