Plasma discharge in contact with water is a promising technology for disinfection. Developing efficient gas-liquid nonthermal plasma reactors for disinfection is very urgent. In this work, a plasma-assisted rotating disk reactor (plasma-RDR) was developed toward disinfection of Escherichia coli (E. coli). Experimental results show that the number of killed E. coli increased by 3.07 x 10(5) CFU.mL(-1) within 60 min when the rotational speed increased from 0 to 500 rpm. Effects of discharge characteristics and other operating conditions on the disinfection efficiency were evaluated. Synergistic effects of plasma and acid or alkali on the disinfection efficiency were obvious. Based on the Weibull distribution model, the critical pH values of resistance were approximately 10.4 and 5.3. The main disinfection process of cell electroporation was inferred based on observations of the cell morphology. Compared with other reported plasma reactors and disinfection technologies, plasma-RDR has better disinfection efficiency at a lower energy consumption.