Quasi-star, also known as black hole star, is hypothetically star are believed to have only existed of beginning of the universe when most a the material in the galaxy was hydrogen and helium. A Quasi-star could be as large as 10 billion kilometers or roughly large than 7.000 times the radius of the sun. Quasi-star is supermassive star with a central black hole and are both considered as potential progenitor for the formation of supermassive black hole. They are expeted to form from rapidly accreting protostars in massive primordial halos.