An interior corridor and a block engraved with 10 hieroglyphic lines were among the finds at the Dahshur royal necropolis, south of Cairo.
The ministry said they were in very good condition and that excavation work was continuing to try to reveal more and establish the size of the pyramid.
It was is believed to have been built during the 13th pharaonic dynasty.
Dahshur is where King Sneferu built ancient Egypt's first true smooth-sided pyramid, the 104m-high Red Pyramid, about 4600 years ago.
