The invention discloses an evidence obtaining method based on electronic signature data. The evidence obtaining method comprises the steps that the electronic signature data are verified to generate evidence obtaining data; when the electronic signature data are verified, generation time of the evidence obtaining data is verified, a timestamp is obtained, a verification process is recorded, and therefore evidence obtaining recording information is obtained; a preset electronic file is generated according to the evidence obtaining data, the timestamp and the evidence obtaining recording information; the preset electronic file is recorded and stored. According to the method, it can be guaranteed that an evidence obtaining result is safe, reliable and believable. The invention further provides an evidence obtaining system based on the electronic signature data.