Internet service providers MTNL, BSNL and Airtel have confirmed difficulties in accessing these sites, according to a report from ZDNet.
The reports say the decision behind blocking the websites appears to be piracy. Most of the websites affected are widely used to share film and music content.
The reports come within a day of India signing a memorandum of understanding with the US to collaborate on cybersecurity issues.
The Department of Homeland Security has made similar moves against piracy by seizing domains of websites hosting pirated content.
The cost of piracy to the Indian entertainment industry was estimated at between $1 and $2 billion, according to a report by The Times of India.
This story was first published by Computer Weekly