In the past,″doctrine of fact″had commonly been used in academic field to refer to the interpretation of the concept of evidence,which is provided in the Criminal Procedure Code .This view claims that evidence is fact which is used to prove the truth situation of a case .However,in the eyes of the opponent of this doctrine,the essence of″doctrine of fact″lies in emphasizing the truth of evidence,so it not only breaches the epistemology of dialectical materialist,but also is inconsistent with the logic and practice of applying evidence .With the amendment of the Criminal Procedure Code in 2012,″doctrine of fact″was replaced by″doctrine of material″as a statutory definition of the concept of evidence .″Doctrine of material″avoids analyzing the truth of evidence,as whether it is true or not,any ″material″can be considered to be evidence in procedure .This change will give rise to a risk that the proposition that evidence must be true,which is derived from″doctrine of fact″would be negated .In fact,the interpretations of the concept of evidence in these two doctrines are simply applying the epistemology of dialectical materialist without discrimination .They concentrate on the question whether the″objective truth,″which is subject in full accordance with object,can be realized .Therefore,they fall into the ontological and metaphysical way of thinking,and are difficult to justify themselves .Applying the inter-subjectivity theory of modern epistemology,a new way of interpreting the truth of evidence will be found .From the perspective of this theory,the purpose of cognitive activity is to form a reasonable and acceptable result of cognition by means of inter-subjective evaluation and identification,but not to seek the absolute truth of the content of cognition .In the light of this theory,the truth of evidence must be interpreted as″alleged truth,″that is,a positive judgment made by the procedure subject who tenders evidence in the way of word or statement .Only having the quality of″alleged truth,″can evidence enter a procedure and become cognitive object of each procedure subject .″Alleged truth″is not objective truth,but is a sort of positive judgment or conclusion made by the subject who cognizes evidence that the content of cognition accords with the object of cognition .However,it does not mean that the subject who cognizes evidence can affirm or promise the truth of evidence arbitrarily .If the truth of evidence is interpreted as″alleged truth,″it will be found that,the opinion which″evidence must be truth″neither breaches the epistemology of dialectical materialist,nor contradicts the logic and practice of applying evidence .There are a variety of methods to define the concept of evidence,and it is unsuitable to define this concept in a standard and unified way of legislation .Under the background that the definition of the concept of evidence is still provided by Chinese legislation,it is very important to contain and accept the various interpretation of the truth of evidence .″Evidence must be truth″can be reasonably explained bases on″alleged truth″in theory and logic,and″alleged truth″can also guide the parties to produce evidence truthfully and the trial subject to evaluate and judge the evidence discreetly .