I am a Visiting Research Professor on J1 visa. I will be in US for less than six months and will be returning back to India after that. I am exempt from US federal Tax as per Indo-US treaty, but after going back to India do I have to pay income tax on the money earned in US?

Tax treaties exist to avoid double taxation. If you claim the treaty in the US you have to pay taxes in your country of residence if this kind of income is taxable there.

What TaxesForAlien says is essentially true, but income earned under a J-1 visa as a visiting professor is tax-exempt in BOTH countries under the U.S.-India Tax Treaty. That is probably the underlying reason why there is a two-year cap on the duration of the stay in the treaty itself.

What ATE says is essentially not true, because the U.S.-India Income Tax Treaty exempts only U.S. income tax for an Indian visiting professor in the U.S. The treaty does not say anything about exempting Indian tax in that situation. While Indian tax law may or may not tax the visiting professor, the treaty does not prevent Indian taxation.

I will not contest IntlTax on his post, because I really do not know (in that I cannot cite the indian tax law per se) whether the Indian tax system would try to tax the visiting professor's income.

However, it is my understanding that India does NOT tax earned income that originaites OUTSIDE of India if the Indian citizen leaves the country for a set period of time; I believe the requisite time spent outside of the country is six months. If that rules applies for visiting professors, then India would make no attempt to tax the earned income.

Article 21(2) of the us-india income tax treaty is only for students and business apprentices