[The subchronic toxicity study on the biological amnion]. As the new type cornea ulcer renovation material, the biological amnion is to be implanted into the human body for a long time, a subchronic toxicity study in rats is made to evaluate its possibility of subchronic toxicity. The study is based on the requirements of "Biological Evaluation of Medical Devices, Part 11: Tests for systemic toxicity and Part 6: Tests for local effects after implantation". After the implantation of examples to be tested, animals were observed daily for mortality and 92 days later the possible subchronic toxicity was evaluated. And a necropsy was conducted and the selected organs were excised, weighed, and processed histologically. Body weights, organ weights, organ/body weight ratios, hematology values and clinical chemistry values were analyzed statistically. Results show that daily clinical observation, body weights, necropsy findings, organ weights and organ/body weight ratios were within acceptable limits in test and control treatment groups. There were no obvious changes in histopathology, hematology values or clinical chemistry values in either male or female rats and no notable differences between the biological amnion and the control amnion. This study proves that, the cornea ulcer renovation material, the biological amnion does not induce subchronic toxicity.