A non-magnetic single-component toner 8 of the present invention has toner mother particles 8a, and external additives 12 comprising: two hydrophobic silicas 13, 14 of which particle diameters are different from each other, i.e. a mean primary particle diameter of 7 nm to 12 nm and a mean primary particle diameter of 40 nm to 50 nm, and a hydrophobic rutile/anatase type titanium oxide 15 having a spindle shape of which major axial diameter is in a range from 0.02 nm to 0.10 nm and the ratio of the major axial diameter to the minor axial diameter is set to be 2 to 8, wherein the external additives 12 adhere to the toner mother particles 8a. By the hydrophobic silicas 13, 14 having work function smaller than the work function of the toner mother particles 8a, the negative charging property is imparted to the toner mother particles 8a and the fluidity is also insured. On the other hand, by mixing and using hydrophobic rutile/anatase type titanium oxide particles 15 having work function larger than or equal to the work function of the toner mother particles 8a together with the hydrophobic silicas 13, 14, the non-magnetic single-component toner 8 is prevented from excessively charged. Therefore, the amount of fog toner on non-image portions is reduced, the transfer efficiency is further improved, the charging property is further stabilized, and the production of reverse transfer toner is further inhibited.