An artificial marble is herein disclosed which comprises a polymer (A) of a radical polymerizable vinyl compound, an inorganic filler (B) having an average particle diameter of 1 μm or more, and a colloidal metal oxide (C) having an average particle diameter of 1 to 100 nm, the metal oxide (C) being uniformly dispersed in the state of substantially primary particles in the polymer (A). The colloidal metal oxide (C) can be uniformly dispersed, whereby a high flame retardancy can be imparted to the artificial marble, and the inorganic components can be filled in a higher ratio without impairing aesthetic properties peculiar to the artificial marble.