A developing method for converting an electrostatic latent image on the surface of an electrostatic latent image holder into a visible image by arranging the electrostatic latent image holder for holding the electrostatic latent image thereon and a toner conveyor for conveying non-magnetic one-component type toner thereon an extremely small space apart from each other; applying the non-magnetic one-component type toner onto the toner conveyor; and transferring the toner to the electrostatic image holder, satisfies the following requirements: the aforesaid developing agent is composed of non-magnetic type toner; the frictional charge quantity relative to the surface of the non-magnetic type toner is +30 100 .mu.C; and fluidity is 5 g or less in terms of the toner amounting to 20 g but remaining on a 100-mesh sieve after it has been vibrated at a rate of 3,000 V.P.M. and an amplitude of 1 mm for 30 seconds. The non-magnetic one-component type toner may positively charged non-magnetic one-component type toner at least containing resin and a coloring agent, the resin satisfying the following requirements: the glass transition point is over 50.degree. C.; the softening point is within the range of 110.degree. C.-160.degree. C.; and the frictional charge amount relative to the surface area is within the range of 25.about.150 .mu.C/m.sup.2. The non-magnetic one-component type toner may be prepared by treating the surface of toner containing binder resin whose glass transition point is over 50.degree. C., and whose softening point is within the range of 110.degree..about.160.degree. C., and a coloring agent with a silane coupling agent having an amino group.According to the above method, development fog and the scattering of the toner are prevented so that a visible image of good quality can be formed.