Salma bint Hizab al-Oteibi was elected to the council of Madrakah, a region in the holy city of Makkah, the official SPA news agency reported, citing election commission president Osama al-Bar.
She was running against seven men and two women, he added.
Saudi Arabia is an absolute monarchy with some of the world’s tightest restrictions on women, including a ban on driving.
It was the last country to allow only men to vote, and polling stations were segregated during Saturday’s vote.
Among the 6,440 candidates were more than 900 women, who overcame a number of obstacles to participate in the landmark poll.
Female candidates could not directly meet any male voters during their campaigns.
Female voters said registration was hindered by factors including bureaucratic obstacles and a lack of transport.
As a result, women accounted for less than 10 percent of registered voters and few female candidates were expected to be elected.