The invention discloses a cloud platform safety quantitative evaluation method based on an improved VIKOR method. The cloud platform safety quantitative evaluation method comprises the following steps of S1, determining the index system and attribute of cloud platform safety quantitative evaluation; S2, preprocessing index attribute data, and establishing an evaluation basis matrix; S3, converting the evaluation basis matrix into a standardized decision matrix; and S4, establishing a cloud platform safety evaluation model, and obtaining the evaluation result ranking index of each evaluation scheme in dependence on the evaluation model. Aiming the characteristic, of the cloud platform, that each evaluation factor has dynamic nature and relevance, a new decision matrix establishing method is provided, and therefore defects and deviations of a conventional VIKOR decision matrix processing method in the evaluation information set aspect can be overcome, scientificity, objectivity and comprehensiveness of safety evaluation can be obtained at the same time, and the accuracy of the cloud platform safety evaluation result can be improved.