Al-Akbar Mosque (Indonesian: Masjid Al-Akbar, lit. 'Great Mosque'; Arabic: المسجد الأكبر‎; Javanese: ꦩꦼꦱ꧀ꦗꦶꦢ꧀ꦄꦭ꧀ꦄꦏ꧀ꦧꦂ), also known as Great Mosque of Surabaya, is a national mosque located in Surabaya, East Java. It is the second largest mosque in Indonesia after Istiqlal Mosque in Jakarta in terms of maximum capacity. The location of the mosque is beside the Surabaya-Porong Highway Road. Its most distinctive feature is its large vertical dome, accompanied by four small blue domes. It also has a minaret with height of 99 meters, an ode to the 99 Names of Allah.

The groundbreaking was initiated on August 4, 1995, after the idea by Soenarto Soemoprawiro, the Mayor of Surabaya at the time. The construction was marked by the laying of the first stones by Try Sutrisno, the Vice President of Indonesia. Due to the 1997 Asian financial crisis however, the construction was temporarily suspended. The construction was resumed in 1999 and completed in 2000. On November 10, 2000, inauguration was held by the President of Indonesia, KH. Abdurrahman Wahid.

In terms of area, the building and supporting facilities combined are 22,300 square meters wide. The building has length of 147 meters and width of 128 meters. The roof consists of a large dominating dome supported by four small domes and a minaret. The uniqueness of this dome is in its shape which almost resembles a half egg with 1.5 layers which has a height of around 27 meters. To cover the dome, a product that was used for several other mosques such as Selangor Grand Mosque in Shah Alam, Malaysia was also utilized. Other features of this gigantic mosque include the entrance into the high and large rooms of the mosque and its mihrab which is the largest in Indonesia.