| With the development of economy, as well as the impact of economic globalization, the situation of competitive pressure for the SMLE (Small and Medium-sized Logistics Enterprises) is more serious. More and more SMLEs have realized that it difficult to survive on their own and adapt to the complex and ever-changing competitive environment. Strategic alliance is an effective method to enhance SMLEs' competitiveness. To a greater extent, in the form of strategic alliance, SMLEs could share of their logistics resources and obtain more revenue of which the single SMLE cannot achieve. Through the formation of strategic alliances, the relationship between the SMLEs is strategic collaboration: to trust of each other, to share risk and income. But many SMLEs do not dare to have a try, because of the high-risk and high failure rate of the strategic alliance. So it is essential and necessary to research on the risk involved in the strategic alliances. In the course of the research on strategic alliances, we can sum up the causes of the failure and find out effective preventive measures, so there is great practical significance.The thesis will research on the causes of risk factors, risk assessment methods and mechanisms theoretically, to prevent risk of SMLE strategic alliances. The methods or theory maybe used comprehensively in the thesis are bellow: theory of strategic alliances, theory of risk management, and varieties of qualitative research and quantitative evaluation methods. Based on the stage theory of strategic alliances, the thesis analyzes the factors and the causes, and constructs the game model of credit risk of the strategic alliances in SMLE; the thesis puts forward the evaluation index system and improves the quantitative evaluation model of risk of strategic alliances in SMLE; the thesis also gives out the risk-prevention system for the strategic alliances and preventive measures at different stages of strategic alliances in SMLE.There are four main innovations in the thesis: first of all, propose the dynamic cycles about strategy alliances based on the elaboration on relevant theories of strategic alliances and strategy management; secondly, construct the index system of risk evaluation, on the base of analysis of risk factors at different stages of strategic alliances; thirdly, improve the risk evaluation model; the last one, put forward the counter-measures and the precautions-system to minish the risk of strategic alliances of SMLE. |