In the present study, the low pollution acidic potassium permanganate system has been used in the study of its micro‐etching effect on polycarbonate‐acrylonitrile butadiene styrene (PC‐ABS). Prior to micro‐etching using a N methyl pyrrolidone (NMP)‐glycol butyl ether solution was used as the swelling system of PC‐ABS. Reasonable swelling conditions were determined, a 2‐min expansion period at a temperature of 35°C with an NMP concentration of 80%. After the swelling processes, the effects of the volume ratio of :, micro‐etching temperature, and micro‐etching duration on the PC‐ABS surface morphology, surface roughness, surface hydrophilicity, and peel strength, have been investigated. It was finally determined that the best micro‐etching effect could be obtained by reacting at : = 1:2 and a temperature of 60°C for 25 min. The surface of the PC‐ABS copolymers was characterized by x‐ray photoelectron spectroscopy, atomic force microscopy, and Fourier‐transform infrared spectroscopy. The results showed that the micro‐etching process changed the morphology of the PC‐ABS surface and generated cavities. In addition, the surface roughness increased from the initial Ra = 9.69 to Ra = 197 nm. Also, the water contact angle on the PC‐ABS surface decreased from 92.2° to 28.6°, and the peel strength increased to 0.98 kN/m.