It depends how you define "God." Judeo-Christian religions are generally understood to believe in the same God. This includes Judaism, Christianity, and Islam, as well others such as the Baha'i faith and the Rastafari movement. All of these faiths share a substantial amount of mythology, although each has its own perception of it and has additional beliefs that make each faith unique.
The African Diaspora religions also acknowledge a deity they equate to the Christian god, as their faiths are combinations of traditional African religion and Catholicism. These religions include Vodou, Candomble, and Santeria.
Read more: Bondye, The Good God of VodouIn addition, there are other religions that are monotheistic but have a mythology that is entirely separate from Judeo-Christian belief. Some people view monotheistic god of these faiths as equivalent to the Judeo-Christian god. Zoroastrianism is the most notable of these religions, whose followers are considered People of the Book by some Muslims despite the fact that Muslims and Zoroastrians do not actually share any holy texts.
Read more: Ahura Mazda, God of the Zoroastrians