The object resembling a plane door featuring Chinese symbols, was discovered by a passerby in Saint Denis, the island's capital, The Guardian reported.
The news about the finding of the plane door came from Freedom Radio station, which was informed by a caller that he had found "a large metal object with foreign writing".
The new wreckage was found 25 km from Saint Andre, where the first piece of debris -- a two-metre, barnacle-encrusted flaperon or the wing component of an aircraft -- was found on July 29. It has been sent to the French city of Toulouse for further analysis.
Preliminary results are expected by Wednesday.
Meanwhile, Malaysia Airlines on Sunday said the flaperon has been confirmed as being from a 777 plane.
"We know the flaperon has been officially identified as being part of a Boeing 777 aircraft. This has been verified by French authorities together with aircraft manufacturer Boeing, the US National Transportation Safety Board and a Malaysian team comprising the department of civil aviation, Malaysia Airlines, and Malaysian ICAO annex 13 safety investigation team for MH370," Malaysian Transport Minister Liow Tiong Lai said.
A church service was held at Cambuston church in Saint Andre on Saturday in memory of the 239 people on board the Kuala Lumpur-Beijing flight which mysteriously disappeared from the radars on March 8, 2014.
Over 400 people attended the service at the church, which is located close to the beach where the first piece of wreckage was discovered.