Abstract: Cellulose acetate (CA) is a significant biobased sustainable polymer with environmentally friendly, renewable, easily degradable and biocompatible features, which plays a crucial role in various fields. For example, it is widely used in the manufacture of a wide range of polymer materials, such as textiles, membranes, and cigarette filters. However, the narrow processing temperature range of CA polymers, due to the proximity between the viscous flow temperature (T_f) and decomposition temperature (T_d), leads to difficulties in melt processing and limits the development of mechanically strengthened CA materials. Introducing crosslinking agents to establish covalent crosslinked networks is an effective approach to enhance the mechanical properties of CA materials, which is essential for the development of high-performance CA materials. However the covalent crosslinked network also restricts the re-processability of CA materials. In this work, a small amount of poly(vinyl alcohol) (PVA) and boric acid (BA) were employed to construct a novel dynamic crosslinked CA-BA-PVA material based on reversible covalent borate ester bond via solution processing under mild conditions. This method is simple, efficient, and maintains the appearance of CA materials unchanged. The results demonstrated that the introduction of the above reversible crosslinked polymer network enhanced many properties of CA materials, such as thermal stability, rheological property, creeping resistance and tensile strength, compared with unmodified cellulose acetate. Furthermore, due to the establishment of a dynamic crosslinked network, the CA materials exhibited good re-processability. They could be recycled three times without losing transparency and mechanical strength.