They were received by Prime Minister Manmohan Singh and his wife Gursharan Kaur, in a departure from the usual protocol.
The Japanese royal couple, on a six-day visit, are accompanied by a delegation of 50 including former Japanese prime minister Yoshiro Mori.
Officials in the ministry of external affairs said the visit is very high in "symbolism and goodwill" and no "political or any other contemporary" issues are expected to be discussed.
External Affairs Minister Salman Khurshid will be the minister-in-waiting for the visiting dignitaries. The royal couple will also visit Chennai.
The ties between India and Japan have been on the upswing.
Dr Singh had visited Japan in May during which both sides had agreed to further enhance cooperation in diverse fields, particularly in trade and investment.
Image: Japan's Emperor Akihito, Empress Michiko with Prime Minister Manmohan Singh and his wife Gursharan Kaur at the airport in New Delhi ' Photograph: Adnan Abidi/Reuters
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