Background and Aim: The Cartagena Protocol on biosafety has been formulated based on the precautionary principle. Following Iran's accession to the Protocol, the Iran Biosafety Act was adopted to establish regulations in this field. In spite of the necessity of complying of this law with the precautionary principle, its adherence to this principle is in doubt. Therefore, the present study seeks to investigate the extent of its compliance with the precautionary principle by analyzing this legal document. Materials and Methods: In this analytical study, while studying the literature and published articles, the document of biosafety law was analyzed and criticized from different aspects. Findings: In this law, the ethical principle of precaution and its scope and how it is enforced has not been mentioned and only implicitly it has been mentioned for risk assessment and management by referring to the Cartagena Protocol. In the area of public participation, there are also no requirements and there are many ambiguities regarding compliance with the precautionary principle regarding civil and criminal liability. Conclusion: The biosafety law has failed to enforce the precautionary principle and is in contradiction with the aforementioned approach. The main reason for this matter may be the lack of definition and scope of this principle in view of the socio-economic conditions of the country. Amendments of the law are recommended in accordance with the precautionary principle.