PURPOSE: To manufacture cadmium sulfoselenide for electrophotography whose granular form is uniform and grain size is equal by adding a mixed flux of NaCl and CdCl2 under a specified condition to a mixture consisting of In-contg. CdS and CdSe and calcining the mixture and treating the calcined substance with aqueous ammonia and calcining it again.

CONSTITUTION: ≥20wt% preferably 30W50wt% mixed flux consisting of NaCl and CdCl2 is added to a mixture of CdS and CdSe contg. about 10W20×10-4mol In and Cu respectively per 1mol and the mixture is calcined at the temp. higher than the m.p. of the flux by ≥50°C (preferably at about ≤600°C). Then, the resulting cadmium sulfoselenide powder is added in aqueous ammonia of about 0.3W0.8mol/l concn. at the rate of about 5W200g per 1l treatment soln. and dispersed under stirring and preferably ultrasonic wave is superposed thereto. After the treatment has been finished, the powder is calcined again at about 400W 450°C.