Abstract: The construction of a unified national market requires the elimination of judicial local protectionism as a judicial guarantee. The existence of judicial local protectionism hinders the free flow and efficient allocation of resource factors, restricts the high-quality development of the economy, and jeopardizes the construction of a unified national market. In order to eliminate judicial local protection, China has vigorously pushed forward the reform of the judicial system, but there still exists such practical dilemmas as the rough design of the reform system of the provincial unified management of human resources and materials, the production of guiding cases subject to the influence of territoriality, the de-localization function of the circuit courts is still weak, and the degree of judicial openness and judicial supervision is not sufficient. The formation of judicial local protectionism is the result of multiple factors, including institutional factors, financial factors, power structure factors, organizational structure factors, legislative system factors, and regional cultural factors. In view of the existing difficulties and the causes of judicial protectionism, it is recommended that reforms be carried out at three levels, namely, upgrading and optimizing institutional safeguards, creating a fair judicial environment and deepening practical measures, with a view to advancing the process of building a unified national market.