In order to maximize the value of BIM-based construction management platform, this paper studies the quantitative evaluation of platform information quality based on the current development of BIM-based construction management platform. Through analyzing and selecting the evaluation elements, designing the evaluation level, and using AHP to establish evaluation model, this paper puts forward an evaluation method on information quality of the BIM-based construction management platforms. The evaluation method has been applied in the management based on BIM construction management platform of the construction project of Jiuzhaigou-Mianyang Expressway in Sichuan Province. The evaluation results quantitatively reflect the quality of information input by each unit of the platform, and indirectly improve the quality of platform information, which verifies the effectiveness of the evaluation method.