The King Fahd Causeway (Arabic: جسر الملك فهد, romanized: Jisr al-Malik Fahd) is a 25 km (15.5 mi) long series of bridges and causeways connecting Khobar, Saudi Arabia and Al Jasra, Bahrain.

Its five bridges rest on 536 concrete pylons, with seven embankments in the Gulf's shallower water. One of the embankments, known as Middle Island (الجزيرة الوسطى, al-Jazirat al-Wustaa) has been converted into a sizeable artificial island with customs and immigration facilities, a mosque and gardens and fast food restaurants. Another island towards the end of the causeway belongs to Bahrain and is simply known as Mother of Sleepiness (ام النعسان, Um al-Na'saan).

Since 8 March 2020, as a result of the COVID-19 pandemic, the causeway is temporarily closed down to all passenger traffic in order to stem the spread of the COVID-19 virus between the two countries. Commercial cargo trucks are still allowed to cross the border following stringent checks. The causeway reopened on 23 July 2020, and Saudi Arabia's embassy in Bahrain announced that citizens can return to the Kingdom via the King Fahd Causeway without prior permission. On 10 September 2020, the causeway is listed as closed to most non-commercial traffic on the U.S. Embassy in Bahrain website.