"The papers (evidences), on which basis, NIA had given the clean chit to Sadhvi Pragya Singh and five others in the Malegaon blast case, should be re-investigated," said Athwale.
The Rajya Sabha MP said that someone should approach court over the "credibility" of the evidences relied upon by the premier investigative agency.
The NIA had on Friday dropped all charges against Sadhvi and five others while charges under the stringent MCOCA law were given up against all the other 10 accused, including Lt Col Prasad Shrikant Purohit.
Athawle's party is a constituent in the BJP-led NDA government in Maharashtra.
On the Narendra Modi government completing two years in power later this month, Athawle said, "though government has failed to bring black money back, the PM is doing a lot of work and the image of India at global level is being elevated".