The formation of animation is to separate a series of related actions and play them in series, so that the naked eye can produce visual images under the condition of residue and produce illusions in the activities, which is considered as a special form of dynamic expression. Whether a producer can accurately grasp the time and rhythm of the work in the picture determines the success or failure of the work.

In fixed cell animation, its production method is unique, and there are stricter requirements on the formation of time and action. Different time intervals will bring different rhythms, and different rhythms determine the tone of the action plot of animation, affecting the overall atmosphere of the film and the final expression of the script creation.

There are many factors that determine the time and the corresponding rhythm of setting each plot in an action animation, including grasping the overall style of the story, the direction of the story change, following the ups and downs of the story, and the effect expression of some special situations. Of course, the most important thing is to respect the physical laws of things.

This paper will focus on the grasp of fixed time and movement rhythm in animation, combining with my actual production experience in graduation design work, focusing on what objective and subjective factors affect the development of time and rhythm of animation in a production process, and it plays a vital role in the quality of a work.