As scientific evidence, expert opinion is an important basis for investigators to solve cases and judges to
decide cases. The current binary verdict and the level of probability used in expert opinions have problems such as exaggerated probability and insufficient scientificity, etc. The likelihood ratio method used in the presentation of
DNA test expert opinions has attracted the attention of court scientists at home and abroad. The likelihood ratio
method is a naturally scientific and legitimate way of expressing the results of identification opinions compared
with the traditional mode of expressing opinions. This paper analyzed the problems of the traditional expert
opinion model and the advantages and shortcomings of the likelihood ratio expert opinion model systematically,
so as to provide reference for the transformation of the scientific evidence evaluation model in the judicial field in
China.