The purpose of this study was to develop an attention sequential mining mechanism for investigating the sequential patterns of children's visual scanning process in a computerized cancellation test. Participants had to locate and cancel the target amongst other non-targets in a structured form, and a random form with Chinese stimuli. Twenty-three children aged between 10-12 years were recruited and took part in this experiment. Sequential pattern analysis for stimulus cancellation revealed that the structured form has a visual guiding effect producing a maximum of 18-sequence in a horizontal scanning pattern. The sequential pattern of the random form, showed no guiding effect, was vertical and yielded only 2- to 4-sequence patterns. The results demonstrated that the organization of stimulus layouts (i.e., structured or random forms) might have implicit visual guiding effects in visual scanning.