To address the issues of data source isolation, format heterogeneity, broken BIM reference relationships, and permission incompatibility when integrating the domestic BIM collaboration platform EWCDE with ProjectWise, this paper designs and implements a dedicated ProjectWise data access module. The module adopts a four-layer domestic architecture consisting of the "application layer - support layer - data layer - infrastructure layer". The three core technologies have been integrated. By cracking the ProjectWise bit mask permission mechanism, the precise mapping with EWCDE atomic permissions is realized. Through static SQL batch insertion and dynamic BatchSize tuning, the efficiency of large-scale data access is improved. By introducing FTP transmission and MD5 verification, the reliability and integrity of cross-server file transmission from ProjectWise to EWCDE storage are guaranteed. The project verification: Baihetan access is only 2h, the efficiency is 75% higher than the traditional manual, the data consistency is 100%, the BIM reference relationship repair rate exceeds 95%, and the file MD5 verification success rate is 100%. The module is suitable for Kirin V10 and Dameng 8, and has supported 20 + projects. The average annual rental and maintenance cost of ProjectWise in a single project is more than 500, 000 yuan.