A process for producing a multilayer varistor having an increased current-carrying area, characterized in that it comprises the following steps: a) spreading a prepared ZnO ceramic slurry into green tapes having a thickness ranged from 10μm tο 100μm by doctor blade technique; b) making a lower cap and an upper cap each having a predetermined thickness (t) via piling plural prepared green tapes of step a) respectively; c) printing an inner electrode on the prepared lower cap of step b) with a margin (h) left around each side edge of the inner electrode; d) piling plural prepared green tapes of step a) onto the lower cap of step c) until a resulting stack has a thickness reaching a predetermined inner-electrode gap (g), and printing an interdigitated inner electrode thereon to leave a margin (h) around each side edge of the inner electrode; e) repeatedly stacking the inner-electrode gap (g) and printing the interdigitated inner electrodes until to obtain an inner-electrode stack having a predetermined number of layers of the inner electrodes; f) placing the preformed upper cap onto the top of the inner-electrode stack, and laminating the lower cap, the inner-electrode stack and the upper cap into a unity as a multilayer varistor green body, and the following conditions are satisfied: f1) the thickness (t) of the lower cap and of the upper cap is smaller than a thickness of the inner-electrode gap (g), but equal to or greater than 0.1 times of the thickness of the inner-electrode gap (g); and f2) the margin (h) left from the inner electrode is smaller than the thickness of the inner-electrode gap (g), but equal to or greater than 0.1 times of the thickness of the inner-electrode gap (g); g) obtaining an MLV sintered body by sintering the MLV green body in a sintering furnace at a sintering temperature of 800-1000°C; h) immersing the MLV sintered body into an alkali metal ion solution having a concentration of 5-80% for at least 2 minutes, and, after dried, performing a step of high-temperature diffusion of low-valence alkali metal ions at a temperature of 650-900°C; i) attaching outer electrodes to two ends of the MLV sintered body made in Step h), and sintering the MLV sintered body at 600-950°C to obtain a final produced multilayer varistor. a) spreading a prepared ZnO ceramic slurry into green tapes having a thickness ranged from 10μm tο 100μm by doctor blade technique; b) making a lower cap and an upper cap each having a predetermined thickness (t) via piling plural prepared green tapes of step a) respectively; c) printing an inner electrode on the prepared lower cap of step b) with a margin (h) left around each side edge of the inner electrode; d) piling plural prepared green tapes of step a) onto the lower cap of step c) until a resulting stack has a thickness reaching a predetermined inner-electrode gap (g), and printing an interdigitated inner electrode thereon to leave a margin (h) around each side edge of the inner electrode; e) repeatedly stacking the inner-electrode gap (g) and printing the interdigitated inner electrodes until to obtain an inner-electrode stack having a predetermined number of layers of the inner electrodes; f) placing the preformed upper cap onto the top of the inner-electrode stack, and laminating the lower cap, the inner-electrode stack and the upper cap into a unity as a multilayer varistor green body, and the following conditions are satisfied: f1) the thickness (t) of the lower cap and of the upper cap is smaller than a thickness of the inner-electrode gap (g), but equal to or greater than 0.1 times of the thickness of the inner-electrode gap (g); and f2) the margin (h) left from the inner electrode is smaller than the thickness of the inner-electrode gap (g), but equal to or greater than 0.1 times of the thickness of the inner-electrode gap (g); f1) the thickness (t) of the lower cap and of the upper cap is smaller than a thickness of the inner-electrode gap (g), but equal to or greater than 0.1 times of the thickness of the inner-electrode gap (g); and f2) the margin (h) left from the inner electrode is smaller than the thickness of the inner-electrode gap (g), but equal to or greater than 0.1 times of the thickness of the inner-electrode gap (g); g) obtaining an MLV sintered body by sintering the MLV green body in a sintering furnace at a sintering temperature of 800-1000°C; h) immersing the MLV sintered body into an alkali metal ion solution having a concentration of 5-80% for at least 2 minutes, and, after dried, performing a step of high-temperature diffusion of low-valence alkali metal ions at a temperature of 650-900°C; i) attaching outer electrodes to two ends of the MLV sintered body made in Step h), and sintering the MLV sintered body at 600-950°C to obtain a final produced multilayer varistor.