Electronic signature plays a key role in the validity of electronic evidence and provides elements such as assigning the document to the issuer, his identity and the integrity of the document. There are different types of electronic signature including simple, biometric and cryptography based with different levels of security. The probative value of a signature depends on the technology and its ability to authenticate the document. Electronic evidence has unique features such as the possibility of being different from the printed version, the possible existence of hidden information, and the uncertainty of attribution to the author. For citation, the author's identity and credibility, including the originality and completeness of the proof, must be verified, which secure electronic signatures and cryptography guarantee. Acceptance of such evidence in court requires ensuring authenticity and integrity through electronic signature and encryption. The collection of these evidences is done in various ways, including access service providers, inspection and seizure of computer systems, and wiretapping of communications, which makes it necessary to respect privacy. Laws such as Iran's e-commerce law have specified the conditions and limitations of accepting electronic evidence, which we will examine in this research using a descriptive and analytical method.