A dental resin material mixed with a composition containing, as a maincomponent, titanium dioxide whose surface has been partly coated with apatite. In the dental resin material, it is preferable that anatase-, rutile-, brookit-type titanium dioxide or a mixture of these components is used as the titanium dioxide. The apatite for partial coating of titanium dioxide is produced by immersing powdery titanium dioxide in a pseudo body fluid and stirring the immersed titanium dioxide approximately at the same temperature as a human body temperature, i.e., 36° C. In this instance, it is important that the apatite is deposited in the form of platy crystals of less than 2 mm in thickness to cover 0.001-10% of the surface of titanium dioxide.