Abstract: A method is provided for processing wastewater having organics even together with high-concentration ammonia-nitrogen, using an apparatus, comprising a catalyzation tank and a subsequent neutralization tank. Organic ammonia-nitrogen wastewater is introduced into tank for reaction without being pre-adjusted by acidic agent or mixing with other additives. A persulfate oxidant is used to process high-efficiency oxidative degradation for ammonia-nitrogen and toxic organics in wastewater through catalyzing oxidation of ultraviolet activation, tiny-amount-transition-metal catalyzation, or both of them, for simultaneous reductions or complete removals of ammonia-nitrogen and organic carbon contents. After neutralization according to actual needs, the final output is complied with biological treatment conditions, discharged-water quality standards, or recycled-water standards.