At present, the application of the variable message sign (VMS) can be undeniably considered as a practical tool for providing travel information to motorists. Several past studies have attempted to examine the effects of socioeconomic and travel characteristics on the diversion behavior; however, the direct investigation of the extent of motorists’ attitudes, in conjunction with the aforementioned variables, has not been well understood and given much attention. Therefore, the primary objective sought in the present study is to gain a better understanding of the interrelationships among the likelihood of making route diversion, attitudinal variables, and several exogenous factors such as socioeconomic and travel characteristics of the motorists. In this study, a structural equation model was developed based on empirical data of road users in Bangkok. Derived from the factor analysis, three attitudinal variables, namely awareness of the VMS, VMS comprehension, and perceived VMS usefulness, were extracted and incorporated into the structural equation modeling framework. Modeling results suggested a direct relationship between stated route diversion and two of the attitudinal variables, i.e. the VMS comprehension and the perceived usefulness of the VMS, while the awareness of VMS was not found to be a direct determinant for route diversion decision. Exogenous variables that appeared to be of statistical significance included education, gender, age, daily mileage, and trip purpose. Unlike past studies, none of the socioeconomic variables in this study appeared to directly influence route diversion intentions. The model estimation results were discussed and practical implications were provided.