A phenothiazine or phenoxazine derivative represented by the following general formula (1), a charge-transporting material comprising the derivative, and an electrophotographic photoreceptor containing the charge-transporting material are disclosed. The charge-transporting material has good solubility in binder polymers, satisfactory sensitivity, and a low residual potential In general formula (1) Ar.sup.1 and Ar.sup.2 may be the same or different and each represents an optionally substituted aryl group; R.sup.1 and R.sup.2 may be the same or different and each represents a hydrogen atom, a lower alkyl group, or an optionally substituted aryl group; R.sup.3 represents a lower alkyl group, an alicyclic hydrocarbon group having 5 to 7 carbon atoms, an optionally substituted aryl group, or an optionally substituted aralkyl group; X represents a sulfur atom or an oxygen atom; and n and m each represents an integer of 0 or 1.