The evaluation of the warning message effectiveness is an important issue in improving communication safety in the system. The goal of the present research was to develop the scale to evaluate the warning message utility, namely, the effectiveness of warning message in preventing accident in general, and an empirical study was conducted to validate the Warning Message Utility Scale (WMUS) in a controlled laboratory environment. The reliability analysis indicated a good the split-half reliability for the WMUS with a Spearman-Brown Coefficient of .873. The predictive validity of WMUS was verified by the significant correlations between the WMUS scores and behavioral indexes of message utility (including reduced kinetic energy and collision rate). The results of regression indicated that the VWMUS is significant predictor of reduced kinetic energy (r2=.339, p<.001) and collision rate (r2=.363, p<.001), which further proved that the validity of WMUS in measuring effectiveness of the warning messages.