Dear Pravin,
If you are staying in India as you mentioned then as per IT laws you are resident in India. All incomes whether Indian or foreign is chargeable to tax in India in case of resident. You will have to pay tax as per slab rates in India :
upto 200000 - Nil
200000 to 500000 - 10%
500000 to 1000000 - 20%
above 1000000 - 30%
Also add EC of 3% to the tax calculated
As you are receiving income from US check whether any Tax is deducted in US. If yes get the appropriate tax credit form and you can claim tax deducted in US as relief from your total tax liability.
Hope this clarifies.