The issue of assessing the quality of judicial decisions is particularly relevant for Russia as for a country at a transitional stage of institutional development. The paper analyzes the factors of quality of judicial decisions through antitrust cases in relation to international practice and Russian specifics. There is an analysis of the main features that determine the quality of the decisions made by the judges on the basis of a unique database of commercial courts cases. The article notes the high significance of the level of specialization and economic competence of judges when considering cases of a certain type. The decision quality factor is based on the minimization of law enforcement errors; and it is determined by such indicators as a fact of appeal, equality of decisions of first and higher instances, as well as a cumulative number of instances considering a case as a parameter of the quality of the case consideration by the judicial system in general. There are several groups of parameters aff ecting the quality. This research is especially focused on individual characteristics of judges, complexity of the approach required to the analysis of a potential violation and sanctions imposed on a party. It is shown that specialized experience of a judge in consideration of cases of a certain type provides rather intensive impact on the decision which will not be canceled by higher instances.