In the realm of marine ecosystems, the pervasiveness of microplastics presents a potential burgeoning global menace to aquatic life forms. This current study sets out to unravel the repercussions of microplastics on the growth, accumulation, and oxidative stress response in the liver of Eriocheir sinensis. To this end, we examined the deposition of fluorescent microplastic particles (with a diameter of 0.5 μm) within the gill, liver, and gut tissues of E. sinensis, which were subjected to a concentration of 40000 μg/L over a period of 7 days. A comprehensive 21-day toxicity assessment showcased a decline in the rate of weight gain, specific growth rate, and hepatosomatic index of E. sinensis with escalating microplastic concentrations (ranging from 0 μg/L to 40000 μg/L). Pertinently, the enzymatic activities of AChE (acetylcholinesterase) and GPT (glutamate pyruvate transaminase) were observed to be lower in crabs exposed to microplastics compared to the control group. Furthermore, GOT (glutamate oxaloacetate transaminase) activity demonstrated an initial surge following exposure to lower microplastic concentrations, followed by a continuous descent as concentrations increased.