Egyptian security sources say the gunmen targeted the checkpoints near the northern town of Sheikh Zuweid.
They were reportedly among military installations attacked two weeks ago by Islamic State-affiliated militants. At least 17 soldiers died in that attack.
Sinai has recently seen a wave of attacks on the Egyptian military.
On Thursday, militants said they carried out a missile attack on an Egyptian naval vessel in the Mediterranean Sea.
The militants, who call themselves Sinai Province, posted pictures online of what looked like a missile followed by a large explosion on the ship.
Egyptian officials said a coastguard vessel caught fire after a fire-fight with militants on the shore.
The army said there were no casualties, contradicting the militants' claim.
Sinai Province was previously called Ansar Beit al-Maqdis (Champions of Jerusalem), but announced a name change in November 2014 when it pledged allegiance to IS, the militant organisation that has taken over large parts of Iraq and Syria.
The group has been on the rise since the military overthrew Islamist President Mohammed Morsi in July 2013, and has killed at least 600 police and armed forces personnel since then.
Islamists kill five at Egypt's Sinai checkpoints - BBC News
