Microsaccades are the largest and fastest of the fixational eye movements during attempted visual fixation. They can overcome visual fading that is due to neural adaptation and play an important role in the process of visual perception and cognition. We designed experiments to explore the difference of the microsaccades on the fixation tasks and attention tasks based on the correlation between microsaccades and visual perception. Comparing microsaccadic parameters in the different difficulty levels in fixation tasks, we found that amplitude, velocity and frequency of macaques' microsaccades are decreased with increasing task difficulty. On the other side, we don't get the same results on the two macaques on comparing the different visual tasks. It represents the different kind of visual tasks maybe lead to the different visual means. This conclusion will provide the basis for the further study on the mechanism of microsaccades.