The present review Summarizes the prominent properties, in particular, the unique optical proper-ties, generated by 9,9-diarylfluorene moiety introduced into polymer main chains in addition to the synthesis of polymers containing diarylfluorene moieties on the basis of results of the studies reported mainly in this decade. Polymers usually show both high refractive index and low birefringence besides many other physical and chemical properties. This review focuses not only on the polymers but also the composite materials, and discloses excellent polymer materials. In addition, synthesis and properties of novel related monomers and their corresponding polymers are also described.