The election is due to start on May 26-27.
Sabahi, who heads a political alliance called the Popular Current, was a member of parliament during ousted autocrat Hosni Mubarak's years in office and came third in the 2012 election that was won by Mohamed Mursi of the Muslim Brotherhood.
Sisi, who led the army overthrow of Mursi in July after mass protests against his rule, is widely expected to win the election as he is viewed by many in the country as the saviour of the people who can bring stability to Egypt.
Sabahi submitted the required documents to the presidential election committee after gathering 31,100 endorsements. The required number of endorsements is 25,000.Sisi submitted his documents last week after gathering 200,000 endorsements.