民事诉讼证据的合法性涉及非法证据有无法律效力以及不符合法律规定的证据是否排除以及如何排除，是一个较为复杂的民事证据理论问题和严肃的司法实践问题。表面上看它仅仅涉及到非法证据的取舍，实际上它与诉讼的基本观念和基本价值选择有着密切联系，并且深受民主法制状况和 The legitimacy of the evidence of civil litigation involves the existence of legal validity of illegal evidence and the exclusion of evidence that does not conform to the law and how to rule out the problem. It is a more complicated issue of civil evidence theory and serious judicial practice. On the surface, it only involves the choice of illegal evidence. In fact, it is closely linked with the basic concept of litigation and the selection of basic values ​​and is deeply influenced by the conditions of democracy and the legal system.