Crystal defects of CVD diamond films are mostly twins, stacking-faults and dislocations. Impurities are mostly morphous carbon, graphite and hydrogen. This paper reviews the research on the crystal defects and impurities. These crystal defects and impurities exist in crystal grains or on grain boundaries. The density of defects and the content of impurities are related with CVD deposition condition. In general, with the increase of CH4 concentration, they increase as well. Impurities either influence the formation of crystal defects. Five-fold twin in CVD diamond is wholly reviewed in the paper at the same time. It will help the research on the crystallology of CVD diamond films.