In order to prevent data security risks in the automotive industry, this paper proposes a multivariate quantitative evaluation method. Firstly, from the perspective of risk sources, the three-dimensional causes of data security incidents in the automotive industry are summarized, and a three-level index system of data security risk assessment in the automotive industry is constructed based on the whole life cycle of data, the whole life cycle of vehicles and the research results of predecessors, including 3 first-dimensional indicators, 6 second-dimensional indicators, and 17 third-dimensional indicators in the third dimension. Secondly, through the questionnaire survey method, the risk matrix method and the Borda ordinal value method, the data security risk level of the automotive industry was ranked and further quantified, and the evaluation results were analyzed from the aspects of overall risk, three-dimensional risk sources and specific risk indicators, and the risk response strategies were studied from the macro and micro levels.