To improve the property of starch film and the additional value of cornstalk, this paper studied the effects of ultrafine grinding time on the composition structure of cornstalk. And 1h ultrafine grinding cornstalk was selected to prepare films with starch. Then the creep and creep-recovery behavior of starch-based films were investigated, to which different content of ball milling cornstalk was added. The results showed that after 1h ball-milling, the fiber bundle and the cell wall of cornstalk can be damaged relatively completely. Comparing with control sample, the particle size and crystallinity were decreased significantly, from 85.33μm to 9.46μm and from 39.46% to 19.29%, respectively. However, with the extension of grinding time, the reunion phenomenon was gradually increased, eventually formed larger particles aggregation. The creep and creep-recovery behavior results indicated that the creep deformation, creep compliance, and irreversible deformation were decreased with the increase of the cornstalk content untill reached 15%.When the content was up to 20%, the anticreep behavior trended to be weaken. Finally, fourcomponent Burgers model was used to fit creep strain and time data (R2>0.98).