The Maghain Aboth Synagogue (Hebrew: מגן אבות, translit: Ma'gen Ahvot, "Guardian of Patriarchs" or "Shield of our Fathers") is a synagogue in Singapore. It is located at 24/26 Waterloo Street in Rochor, within the Central Area at Singapore's central business district. Constructed in 1878, it is the oldest and largest Jewish synagogue in Southeast Asia and the second largest in Asia itself, outside of Israel.

Managed by the Jewish Welfare Board, it remains to be the main place of worship for the Jewish community in Singapore.^[1] It was designated as a national monument of Singapore in 1998. Today, the synagogue and its surroundings has served as the unofficial centre of Jewish activity in Singapore, with several Jewish buildings standing within its vicinity, including a kosher supermarket and a museum.

As Jewish men and women worship separately in an Orthodox synagogue,^[1] the synagogue's original single-storey building could only accommodate men.

The U-shaped second-storey balcony was originally made up wooden slats of makeshift nature which the women were able to see through very clearly. Therefore, the original simple design was deemed inadequate and thus, later constructed to be a solid gallery which was added to the main building which remains in use today.^[15]

The synagogue is a symmetrical building which has adopted a neo-classical style^[16] and colonial architecture.^[7] The design of the building was influenced by the Late Renaissance architectural style in Britain.^[2] The building has a repetitive sequence of Palladian arcades and pedestals^[2] and within the building, the hall has traditional Roman columns and rusticated walls which is bare of any decoration or image.^[7] Along the corners and sides of the building are pilasters topped with decorative capitals. The synagogue's doorways are also adorned with arches with classical keystone architecture.^[2] A covered porch fronts the building with steps leading up to the vestibule originally designed for horse carriages.

Most of the windows are of a similar rectangular design and are timber-louvred. The windows are an important feature of a synagogue because based on the Talmud, Jewish synagogues are required to have windows.^[17] Despite the deliberate simple design of the synagogue, the building still remains to be elegant due to the combination of its timber-louvred windows, marble floors and red carpets with teak and rattan pews.^[18]

The prayer hall is facing west towards Jerusalem and the bimah, an elevated platform in the centre, faces the alcove known as the 'hekhal', which is used to store the Torah scrolls, that is at the West wall of the hall. The parochet which is an embroidered fringed curtain that is rich in details is used to cover the Torah ark. In front of it hangs the sanctuary lamp which signifies the eternal flame that burned in the former Temple of Jerusalem.^[18]

• History of the Jews in Singapore
• Chesed-El Synagogue