This study aimed to investigate the underlying barriers that make Intelligent Transportation System (ITS) project development in Semarang City still hard. Based on previous research, validation process, and accommodating the panel of experts’ request, this study identifies 16 barriers related to ITS project implementation. Then, this study uses interpretative structural modeling (ISM) methodology to find the direct or indirect relationship among the barriers. Data processing with ISM methodology indicated that internal organizational barriers in the timing of procedure for writing plans, divided responsibilities, and the right organizational system to drive ITS occupied the topmost level. This barrier is affected by the lower level and has less influence than the remaining barriers. The result of data processing with ISM methodology also indicated three very significant barrier for ITS project implementation, namely low interoperability of the system at the Department of Transportation Semarang City, which is making it challenging to integrate the ITS-based transportation system; lack of involvement of related institutions to build long-term commitment and awareness that ITS project has potential to reducing, crashes and saving; and political problems (political short-termism or discontinuities due to political cycles).